Nasr M. Ghoniem and Daniel D. Walgraef
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780199298686
- eISBN:
- 9780191720222
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199298686.003.0016
- Subject:
- Physics, Condensed Matter Physics / Materials
This chapter presents the theory of laser-induced deformation and patterning of irradiated surfaces. Topics discussed include laser irradiation and thin film deformation, laser-induced temperature ...
More
This chapter presents the theory of laser-induced deformation and patterning of irradiated surfaces. Topics discussed include laser irradiation and thin film deformation, laser-induced temperature distribution, vacancy dynamics in strained crystals, deformation equations for thin films, variational principle for the free energy, deformation instability and surface patterning, and the influence of crystal anisotropy and adhesion.Less
This chapter presents the theory of laser-induced deformation and patterning of irradiated surfaces. Topics discussed include laser irradiation and thin film deformation, laser-induced temperature distribution, vacancy dynamics in strained crystals, deformation equations for thin films, variational principle for the free energy, deformation instability and surface patterning, and the influence of crystal anisotropy and adhesion.
Jack W. Ekin
- Published in print:
- 2006
- Published Online:
- January 2010
- ISBN:
- 9780198570547
- eISBN:
- 9780191717710
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198570547.003.0007
- Subject:
- Physics, Condensed Matter Physics / Materials
Sample holders provide uniform and stable temperature control of the sample; eliminate sample stress due to differential thermal contraction between the sample and holder; minimize noise from induced ...
More
Sample holders provide uniform and stable temperature control of the sample; eliminate sample stress due to differential thermal contraction between the sample and holder; minimize noise from induced voltages and magnetic pickup by keeping the effective voltage-tap loop area as small as possible; provide well-designed current and voltage contacts, with enough space between each current contact and the nearest voltage lead to ensure that the current distribution is uniform in the region between the voltage taps; and provide firm mechanical support for the sample, particularly for critical-current measurements where large, magnetic Lorentz forces are a major issue. This chapter considers each of these factors in turn, for both bulk sample holders and thin film sample holders, along with examples and design techniques. It also considers the general nature of four-lead measurements, since this technique determines the overall design of most transport-measurement sample holders.Less
Sample holders provide uniform and stable temperature control of the sample; eliminate sample stress due to differential thermal contraction between the sample and holder; minimize noise from induced voltages and magnetic pickup by keeping the effective voltage-tap loop area as small as possible; provide well-designed current and voltage contacts, with enough space between each current contact and the nearest voltage lead to ensure that the current distribution is uniform in the region between the voltage taps; and provide firm mechanical support for the sample, particularly for critical-current measurements where large, magnetic Lorentz forces are a major issue. This chapter considers each of these factors in turn, for both bulk sample holders and thin film sample holders, along with examples and design techniques. It also considers the general nature of four-lead measurements, since this technique determines the overall design of most transport-measurement sample holders.
Robert Blinc
- Published in print:
- 2011
- Published Online:
- January 2012
- ISBN:
- 9780199570942
- eISBN:
- 9780191728631
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199570942.003.0009
- Subject:
- Physics, Condensed Matter Physics / Materials
The development of thin films integrated into semiconductor chips allowed for the development of ferroelectric memories with high information density. The old question of how many unit cells are ...
More
The development of thin films integrated into semiconductor chips allowed for the development of ferroelectric memories with high information density. The old question of how many unit cells are necessary that ferroelectricity, which is a collective phenomenon, does not disappear, thus became important not only for basic physics but also for technology. The film‐thickness dependence of the out‐of‐plane polarization and depolarizing field is presented. It is shown that the retention time due to thermodynamic nucleation of reversed domains imposes a new fundamental size limit for ferroelectric devices that is higher than the critical thickness for the disappearance of ferroelectricity due to depolarizing fields. The Tilley–Žekš model of phase transitions in thin films is discussed and the polarization profiles are presented. The effect of film thickness on the misfit strain induced magnetoelectric coupling is also treated.Less
The development of thin films integrated into semiconductor chips allowed for the development of ferroelectric memories with high information density. The old question of how many unit cells are necessary that ferroelectricity, which is a collective phenomenon, does not disappear, thus became important not only for basic physics but also for technology. The film‐thickness dependence of the out‐of‐plane polarization and depolarizing field is presented. It is shown that the retention time due to thermodynamic nucleation of reversed domains imposes a new fundamental size limit for ferroelectric devices that is higher than the critical thickness for the disappearance of ferroelectricity due to depolarizing fields. The Tilley–Žekš model of phase transitions in thin films is discussed and the polarization profiles are presented. The effect of film thickness on the misfit strain induced magnetoelectric coupling is also treated.
John Orton
- Published in print:
- 2008
- Published Online:
- January 2010
- ISBN:
- 9780199559107
- eISBN:
- 9780191712975
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199559107.003.0010
- Subject:
- Physics, Crystallography: Physics
This chapter discusses two important applications of non-single crystal semiconductors: photovoltaic solar cells and large screen liquid crystal display. The electrical and optical properties of ...
More
This chapter discusses two important applications of non-single crystal semiconductors: photovoltaic solar cells and large screen liquid crystal display. The electrical and optical properties of polycrystalline and amorphous semiconductors are described. Grain boundaries play a major role in determining the behaviour of polycrystalline materials, acting as energy barriers to current flow and as trapping centres for minority carriers. Grain size and doping levels work together with barrier heights to control material properties. Amorphous materials are characterised by lack of order, but can function as semiconductors with low carrier mobilities. Amorphous silicon, containing hydrogen (aSi:H) is used to make thin film transistors, acting as switches at each pixel point in a LCTV display, thus facilitating matrix addressing. It is also used to make cheap solar cells. Crystalline silicon dominates the commercial field of PV solar cells, but is under challenge from a number of polycrystalline materials, such as CdS:CuInSe.Less
This chapter discusses two important applications of non-single crystal semiconductors: photovoltaic solar cells and large screen liquid crystal display. The electrical and optical properties of polycrystalline and amorphous semiconductors are described. Grain boundaries play a major role in determining the behaviour of polycrystalline materials, acting as energy barriers to current flow and as trapping centres for minority carriers. Grain size and doping levels work together with barrier heights to control material properties. Amorphous materials are characterised by lack of order, but can function as semiconductors with low carrier mobilities. Amorphous silicon, containing hydrogen (aSi:H) is used to make thin film transistors, acting as switches at each pixel point in a LCTV display, thus facilitating matrix addressing. It is also used to make cheap solar cells. Crystalline silicon dominates the commercial field of PV solar cells, but is under challenge from a number of polycrystalline materials, such as CdS:CuInSe.
Stephen R. Forrest
- Published in print:
- 2020
- Published Online:
- October 2020
- ISBN:
- 9780198529729
- eISBN:
- 9780191798238
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198529729.003.0008
- Subject:
- Physics, Condensed Matter Physics / Materials, Crystallography: Physics
This chapter lays the foundations of operation of both unipolar and ambipolar organic thin film transistors (OTFTs). Thin film transistors are used in display back planes, digital circuits, memory ...
More
This chapter lays the foundations of operation of both unipolar and ambipolar organic thin film transistors (OTFTs). Thin film transistors are used in display back planes, digital circuits, memory addressing elements, and photodetection. The discussion describes basic transistor principles and the limitations to their performance. Transistor noise and circuit noise margin, cutoff frequency, transconductance, and gain are discussed. Several different lateral architectures including top and bottom gate, and split gate configurations, as well as vertical transistors are described. High performance OTFT materials and channel morphologies and how they are achieved along with contact patterning are discussed. Phototransistors are introduced, and their characteristics are compared with other photodetectors discussed in Chapter 7. Transistor stability and its implication for circuit performance are detailed. Finally, several circuit applications with particular focus on chemical and medical sensing, and communications are described.Less
This chapter lays the foundations of operation of both unipolar and ambipolar organic thin film transistors (OTFTs). Thin film transistors are used in display back planes, digital circuits, memory addressing elements, and photodetection. The discussion describes basic transistor principles and the limitations to their performance. Transistor noise and circuit noise margin, cutoff frequency, transconductance, and gain are discussed. Several different lateral architectures including top and bottom gate, and split gate configurations, as well as vertical transistors are described. High performance OTFT materials and channel morphologies and how they are achieved along with contact patterning are discussed. Phototransistors are introduced, and their characteristics are compared with other photodetectors discussed in Chapter 7. Transistor stability and its implication for circuit performance are detailed. Finally, several circuit applications with particular focus on chemical and medical sensing, and communications are described.
M. E. LINES and A. M. GLASS
- Published in print:
- 2001
- Published Online:
- February 2010
- ISBN:
- 9780198507789
- eISBN:
- 9780191709944
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507789.003.0015
- Subject:
- Physics, Condensed Matter Physics / Materials
The parallel alignment of dipoles in a ferroelectric is due primarily to a relatively strong long-range interaction along the polar c-axis and a weaker shorter-range interaction normal to the axis. ...
More
The parallel alignment of dipoles in a ferroelectric is due primarily to a relatively strong long-range interaction along the polar c-axis and a weaker shorter-range interaction normal to the axis. Physically this comes about because for electric dipolar forces the parallel alignment is energetically favourable for an isolated pair of c-axis dipoles but not for an isolated pair of dipoles normal to the polar axis. Theoretical and experimental estimates can be made of a correlation range, or distance over which near-neighbour-cell polar displacements are strongly correlated in some sense. This chapter deals with ferroelectric thin films and ceramics such as semiconducting ceramics, optical ceramics, and semiconducting ceramics, the grain boundaries of ceramics, effect of impurities on ceramics, and metastable polarization in ferroelectric materials such as electrets, liquid crystals, and pyroelectric polymers.Less
The parallel alignment of dipoles in a ferroelectric is due primarily to a relatively strong long-range interaction along the polar c-axis and a weaker shorter-range interaction normal to the axis. Physically this comes about because for electric dipolar forces the parallel alignment is energetically favourable for an isolated pair of c-axis dipoles but not for an isolated pair of dipoles normal to the polar axis. Theoretical and experimental estimates can be made of a correlation range, or distance over which near-neighbour-cell polar displacements are strongly correlated in some sense. This chapter deals with ferroelectric thin films and ceramics such as semiconducting ceramics, optical ceramics, and semiconducting ceramics, the grain boundaries of ceramics, effect of impurities on ceramics, and metastable polarization in ferroelectric materials such as electrets, liquid crystals, and pyroelectric polymers.
Juan Luis Vázquez
- Published in print:
- 2006
- Published Online:
- September 2007
- ISBN:
- 9780198569039
- eISBN:
- 9780191717468
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198569039.003.0021
- Subject:
- Mathematics, Mathematical Physics
This chapter presents a collection of new examples taken from different branches of science. The first examples come from fluid dynamics, starting with the well-known model of viscous droplets ...
More
This chapter presents a collection of new examples taken from different branches of science. The first examples come from fluid dynamics, starting with the well-known model of viscous droplets spreading by gravity. It then covers topics relating to underground flows important in water management or oil recovery. Attention is given to models of plasma physics. The limits of particle models is also discussed.Less
This chapter presents a collection of new examples taken from different branches of science. The first examples come from fluid dynamics, starting with the well-known model of viscous droplets spreading by gravity. It then covers topics relating to underground flows important in water management or oil recovery. Attention is given to models of plasma physics. The limits of particle models is also discussed.
C. M. Roland
- Published in print:
- 2011
- Published Online:
- September 2011
- ISBN:
- 9780199571574
- eISBN:
- 9780191728976
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199571574.003.0010
- Subject:
- Physics, Condensed Matter Physics / Materials
When a polymer is constrained to spatial dimensions less than roughly 100 nm, its glass-transition temperature often becomes lower than Tg for the bulk state. This effect is well established for ...
More
When a polymer is constrained to spatial dimensions less than roughly 100 nm, its glass-transition temperature often becomes lower than Tg for the bulk state. This effect is well established for free-standing films and often occurs with supported films and material confined within nanopores. The mechanism for the Tg reduction appears to be the enhanced mobility of surface molecules, a result of fewer intermolecular constraints and greater unoccupied volume. However, this explanation cannot account for many details of the phenomenon—the magnitude of the effect depends on the nature of the confining surface, the chemical structure and even tacticity of the material, and its molecular weight. This chapter reviews how spatial confinement affects segmental and chain mobilities, showing how the effects can be dramatic, yet are complex and unaccounted for by any model.Less
When a polymer is constrained to spatial dimensions less than roughly 100 nm, its glass-transition temperature often becomes lower than Tg for the bulk state. This effect is well established for free-standing films and often occurs with supported films and material confined within nanopores. The mechanism for the Tg reduction appears to be the enhanced mobility of surface molecules, a result of fewer intermolecular constraints and greater unoccupied volume. However, this explanation cannot account for many details of the phenomenon—the magnitude of the effect depends on the nature of the confining surface, the chemical structure and even tacticity of the material, and its molecular weight. This chapter reviews how spatial confinement affects segmental and chain mobilities, showing how the effects can be dramatic, yet are complex and unaccounted for by any model.
G Sambandamurthy and N. Peter Armitage
- Published in print:
- 2012
- Published Online:
- September 2012
- ISBN:
- 9780199592593
- eISBN:
- 9780191741050
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199592593.003.0012
- Subject:
- Physics, Theoretical, Computational, and Statistical Physics
DC and finite frequency transport measurements of thin films of amorphous indium oxide that were driven through the critical point of superconductor-insulator transition by the application of ...
More
DC and finite frequency transport measurements of thin films of amorphous indium oxide that were driven through the critical point of superconductor-insulator transition by the application of perpendicular magnetic field are presented. The observation of non-monotonic dependence of resistance on magnetic field in the insulating phase, novel transport characteristics near the resistance peak and finite superfluid stiffness in the insulating phase are all discussed from the point of view that suggests a possible relation between the conduction mechanisms in the superconducting and insulating phases. The results are summarized in the form of an experimental phase diagram for disordered superconductors in the disorder-magnetic field plane.Less
DC and finite frequency transport measurements of thin films of amorphous indium oxide that were driven through the critical point of superconductor-insulator transition by the application of perpendicular magnetic field are presented. The observation of non-monotonic dependence of resistance on magnetic field in the insulating phase, novel transport characteristics near the resistance peak and finite superfluid stiffness in the insulating phase are all discussed from the point of view that suggests a possible relation between the conduction mechanisms in the superconducting and insulating phases. The results are summarized in the form of an experimental phase diagram for disordered superconductors in the disorder-magnetic field plane.
L. Li and X. Pan
- Published in print:
- 2020
- Published Online:
- October 2020
- ISBN:
- 9780198862499
- eISBN:
- 9780191895319
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198862499.003.0010
- Subject:
- Physics, Condensed Matter Physics / Materials, Theoretical, Computational, and Statistical Physics
This chapter presents a review on the recent progress in transmission electron microscopy (TEM) studies of ferroelectric DWs in one of the most widely studied ferroelectric systems — BiFeO3 thin ...
More
This chapter presents a review on the recent progress in transmission electron microscopy (TEM) studies of ferroelectric DWs in one of the most widely studied ferroelectric systems — BiFeO3 thin films. This system has been chosen representative for a much wider range of ferroelectric perovskites with functional DWs, due to its strong spontaneous polarization, coexistence of ferroelectricity, ferroelasticity and antiferromagnetism, and numerous functionalities at the DWs. Here, the chapter first briefly introduces the instrumentation, experimental procedures, imaging mechanisms, and analytical methods of the state-of-the-art TEM-based techniques. The application of these techniques to the study of DW structures and switching behaviors is demonstrated, with particular emphasis on the critical roles of interfaces and defects, and interplay between different types of DWs. The phenomena and mechanism discovered in the model system of BiFeO3 are also applicable to many other ferroelectric materials with similar DW structures. The results not only advance the fundamental understanding of static and dynamic properties of ferroelectric DWs, but also form the basis for designing of practical ferroelectric-DW-based devices.Less
This chapter presents a review on the recent progress in transmission electron microscopy (TEM) studies of ferroelectric DWs in one of the most widely studied ferroelectric systems — BiFeO3 thin films. This system has been chosen representative for a much wider range of ferroelectric perovskites with functional DWs, due to its strong spontaneous polarization, coexistence of ferroelectricity, ferroelasticity and antiferromagnetism, and numerous functionalities at the DWs. Here, the chapter first briefly introduces the instrumentation, experimental procedures, imaging mechanisms, and analytical methods of the state-of-the-art TEM-based techniques. The application of these techniques to the study of DW structures and switching behaviors is demonstrated, with particular emphasis on the critical roles of interfaces and defects, and interplay between different types of DWs. The phenomena and mechanism discovered in the model system of BiFeO3 are also applicable to many other ferroelectric materials with similar DW structures. The results not only advance the fundamental understanding of static and dynamic properties of ferroelectric DWs, but also form the basis for designing of practical ferroelectric-DW-based devices.
A.V. Narlikar
- Published in print:
- 2014
- Published Online:
- June 2014
- ISBN:
- 9780199584116
- eISBN:
- 9780191747496
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199584116.003.0017
- Subject:
- Physics, Condensed Matter Physics / Materials
This chapter focuses on technological compatibility of HTS cuprates and progress made in their thin-film technology and conductor development for practical applications. In order to realise a high ...
More
This chapter focuses on technological compatibility of HTS cuprates and progress made in their thin-film technology and conductor development for practical applications. In order to realise a high Jc(77 K) > 1010 A m−2, deposited HTS films have to be grown with biaxial texturing on suitable single-crystalline substrates. For conductor development, this clearly involves the seemingly impossible task of achieving the required epitaxial growth of HTS films over several kilometre lengths of the metallic substrate. The state of the art of synthesising HTS films using physical and chemical deposition methods is presented and novel techniques for producing unusual multilayer architectures of long HTS conductors are described. The development and present status of first-generation BSCCO conductors are discussed and novel strategies pursued with second-generation coated conductors of YBCO and other potential HTS are presented. The second-generation YBCO conductors have already reached a practical level of their technical applicability.Less
This chapter focuses on technological compatibility of HTS cuprates and progress made in their thin-film technology and conductor development for practical applications. In order to realise a high Jc(77 K) > 1010 A m−2, deposited HTS films have to be grown with biaxial texturing on suitable single-crystalline substrates. For conductor development, this clearly involves the seemingly impossible task of achieving the required epitaxial growth of HTS films over several kilometre lengths of the metallic substrate. The state of the art of synthesising HTS films using physical and chemical deposition methods is presented and novel techniques for producing unusual multilayer architectures of long HTS conductors are described. The development and present status of first-generation BSCCO conductors are discussed and novel strategies pursued with second-generation coated conductors of YBCO and other potential HTS are presented. The second-generation YBCO conductors have already reached a practical level of their technical applicability.
Robert Blinc
- Published in print:
- 2011
- Published Online:
- January 2012
- ISBN:
- 9780199570942
- eISBN:
- 9780191728631
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199570942.003.0008
- Subject:
- Physics, Condensed Matter Physics / Materials
A theory of the electrocaloric effect is presented. It is shown that the electrocaloric effect in ferroelectrics is maximal at the electric‐field‐induced first‐order phase transition, whereas it is ...
More
A theory of the electrocaloric effect is presented. It is shown that the electrocaloric effect in ferroelectrics is maximal at the electric‐field‐induced first‐order phase transition, whereas it is maximal in relaxors at the electric‐field‐induced critical end point. The maximum efficiencies ΔT/ΔE and ΔS/ΔE for various samples are presented. It is shown that in relaxors a giant electrocaloric effect takes place at the critical end point where also the electromechanical response is largest. A universal expression for the maximum temperature change in the saturation regime is derived that is valid both for electrocaloric and magnetocaloric systems.Less
A theory of the electrocaloric effect is presented. It is shown that the electrocaloric effect in ferroelectrics is maximal at the electric‐field‐induced first‐order phase transition, whereas it is maximal in relaxors at the electric‐field‐induced critical end point. The maximum efficiencies ΔT/ΔE and ΔS/ΔE for various samples are presented. It is shown that in relaxors a giant electrocaloric effect takes place at the critical end point where also the electromechanical response is largest. A universal expression for the maximum temperature change in the saturation regime is derived that is valid both for electrocaloric and magnetocaloric systems.
E. R. DOBBS
- Published in print:
- 2001
- Published Online:
- January 2010
- ISBN:
- 9780198506409
- eISBN:
- 9780191709463
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198506409.003.0008
- Subject:
- Physics, Condensed Matter Physics / Materials
This chapter discusses the properties of 3He surfaces and its interfaces with other substances. It presents a selection of experiments and their interpretation is made under six headings: restricted ...
More
This chapter discusses the properties of 3He surfaces and its interfaces with other substances. It presents a selection of experiments and their interpretation is made under six headings: restricted geometry, surface tensions, nucleation, thermal boundary resistance, wetting transitions, and thin films.Less
This chapter discusses the properties of 3He surfaces and its interfaces with other substances. It presents a selection of experiments and their interpretation is made under six headings: restricted geometry, surface tensions, nucleation, thermal boundary resistance, wetting transitions, and thin films.
Tony Whitehead
- Published in print:
- 2012
- Published Online:
- July 2012
- ISBN:
- 9780719072369
- eISBN:
- 9781781703298
- Item type:
- chapter
- Publisher:
- Manchester University Press
- DOI:
- 10.7228/manchester/9780719072369.003.0034
- Subject:
- Film, Television and Radio, Film
This chapter draws attention to Mike Leigh's feature film, Secrets and Lies that proved to be his most popular film, winning the Palme d'Or and the International Critics' Prize at Cannes and ...
More
This chapter draws attention to Mike Leigh's feature film, Secrets and Lies that proved to be his most popular film, winning the Palme d'Or and the International Critics' Prize at Cannes and receiving five Oscar nominations. This chapter draws attention to the fact that this film received a wider UK release than any of his previous work and made huge profit at the box office. The film had also marked a turning point in that it moved Thin Man Films into the European co-production market, funding from the French company CiBY 2000 affording Leigh around twice the budget he had had for his earlier films. Secrets and Lies deals with big issues—among them are love, death, marriage, race, adoption, estrangement and the inability to conceive children.Less
This chapter draws attention to Mike Leigh's feature film, Secrets and Lies that proved to be his most popular film, winning the Palme d'Or and the International Critics' Prize at Cannes and receiving five Oscar nominations. This chapter draws attention to the fact that this film received a wider UK release than any of his previous work and made huge profit at the box office. The film had also marked a turning point in that it moved Thin Man Films into the European co-production market, funding from the French company CiBY 2000 affording Leigh around twice the budget he had had for his earlier films. Secrets and Lies deals with big issues—among them are love, death, marriage, race, adoption, estrangement and the inability to conceive children.
Robert Blinc
- Published in print:
- 2011
- Published Online:
- January 2012
- ISBN:
- 9780199570942
- eISBN:
- 9780191728631
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199570942.003.0003
- Subject:
- Physics, Condensed Matter Physics / Materials
The origin of ferroelectricity in liquid crystals and the basic physical properties of the systems are briefly discussed. Special attention is paid to elementary excitations in ferroelectric liquid ...
More
The origin of ferroelectricity in liquid crystals and the basic physical properties of the systems are briefly discussed. Special attention is paid to elementary excitations in ferroelectric liquid crystals, i.e. the symmetry recovering Goldstone mode, the amplitudon mode and the symmetry‐breaking soft mode. The phase diagram of ferroelectric liquid crystals in magnetic and electric fields is presented and the field‐induced Lifshitz point is discussed. The difference in the soliton structure in electric and magnetic fields is presented. The properties of freely suspended smectic thin films are shown as a function of the number of smectic layers involved. This represents an example of the cross‐over from the 3D to 2D universality class.Less
The origin of ferroelectricity in liquid crystals and the basic physical properties of the systems are briefly discussed. Special attention is paid to elementary excitations in ferroelectric liquid crystals, i.e. the symmetry recovering Goldstone mode, the amplitudon mode and the symmetry‐breaking soft mode. The phase diagram of ferroelectric liquid crystals in magnetic and electric fields is presented and the field‐induced Lifshitz point is discussed. The difference in the soliton structure in electric and magnetic fields is presented. The properties of freely suspended smectic thin films are shown as a function of the number of smectic layers involved. This represents an example of the cross‐over from the 3D to 2D universality class.
Ladislas Kubin
- Published in print:
- 2013
- Published Online:
- May 2013
- ISBN:
- 9780198525011
- eISBN:
- 9780191756238
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198525011.003.0005
- Subject:
- Physics, Condensed Matter Physics / Materials
This chapter presents an overview of significant insights or contributions to modelling provided by three-dimensional dislocation simulations. Four main domains are concerned. A connection has been ...
More
This chapter presents an overview of significant insights or contributions to modelling provided by three-dimensional dislocation simulations. Four main domains are concerned. A connection has been established between elementary dislocation–dislocation interactions and strengthening mechanisms at the scale of bulk specimens. Simulations of dislocation interactions with point defects and small clusters are now reaching maturity. Simulations of precipitation strengthening are quite accurate, and this domain deserves more attention. Large-scale simulations provide unique insights into collective dislocation processes. The areas concerned are dislocation avalanches, dislocation patterns in monotonic and cyclic deformation, dislocation-based continuum modelling and deformation at high strain rates. The understanding of size effects in small-scale materials—in particular, epitaxial semiconductor layers, thin metallic films and micro- and nanopillars—has improved continuously through a synergy between experiment, simulations and modelling. The chapter closes with a short prospective.Less
This chapter presents an overview of significant insights or contributions to modelling provided by three-dimensional dislocation simulations. Four main domains are concerned. A connection has been established between elementary dislocation–dislocation interactions and strengthening mechanisms at the scale of bulk specimens. Simulations of dislocation interactions with point defects and small clusters are now reaching maturity. Simulations of precipitation strengthening are quite accurate, and this domain deserves more attention. Large-scale simulations provide unique insights into collective dislocation processes. The areas concerned are dislocation avalanches, dislocation patterns in monotonic and cyclic deformation, dislocation-based continuum modelling and deformation at high strain rates. The understanding of size effects in small-scale materials—in particular, epitaxial semiconductor layers, thin metallic films and micro- and nanopillars—has improved continuously through a synergy between experiment, simulations and modelling. The chapter closes with a short prospective.
Tony Whitehead
- Published in print:
- 2012
- Published Online:
- July 2012
- ISBN:
- 9780719072369
- eISBN:
- 9781781703298
- Item type:
- chapter
- Publisher:
- Manchester University Press
- DOI:
- 10.7228/manchester/9780719072369.003.0030
- Subject:
- Film, Television and Radio, Film
This chapter illustrates Mike Leigh's feature film Life Is Sweet, an important development in Leigh's working life that came in 1989 when he formed the production company, Thin Man Films, with Simon ...
More
This chapter illustrates Mike Leigh's feature film Life Is Sweet, an important development in Leigh's working life that came in 1989 when he formed the production company, Thin Man Films, with Simon Channing-Williams. For the company's first production, Leigh committed himself to making a comedy that would have a potentially larger audience appeal than his earlier film, High Hopes. Life Is Sweet consolidated Leigh's international reputation as a man of cinema and as a great director of actors. The domestic setting and breezy tone initially gave it the impression of feature-length pilot for, or spin-off from, a situation comedy. With this film, Leigh succeeded in his aim of making a comedy with considerable popular appeal. True, some of the old charges of caricaturing and patronizing his characters were still there, but such criticisms seemed to represent the minority viewpoint.Less
This chapter illustrates Mike Leigh's feature film Life Is Sweet, an important development in Leigh's working life that came in 1989 when he formed the production company, Thin Man Films, with Simon Channing-Williams. For the company's first production, Leigh committed himself to making a comedy that would have a potentially larger audience appeal than his earlier film, High Hopes. Life Is Sweet consolidated Leigh's international reputation as a man of cinema and as a great director of actors. The domestic setting and breezy tone initially gave it the impression of feature-length pilot for, or spin-off from, a situation comedy. With this film, Leigh succeeded in his aim of making a comedy with considerable popular appeal. True, some of the old charges of caricaturing and patronizing his characters were still there, but such criticisms seemed to represent the minority viewpoint.
Stephen R. Forrest
- Published in print:
- 2020
- Published Online:
- October 2020
- ISBN:
- 9780198529729
- eISBN:
- 9780191798238
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198529729.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials, Crystallography: Physics
Organic electronics is a platform for very low cost and high performance optoelectronic and electronic devices that cover large areas, are lightweight, and can be both flexible and conformable to ...
More
Organic electronics is a platform for very low cost and high performance optoelectronic and electronic devices that cover large areas, are lightweight, and can be both flexible and conformable to irregularly shaped surfaces such as foldable smart phones. Organics are at the core of the global organic light emitting device (OLED) display industry, and also having use in efficient lighting sources, solar cells, and thin film transistors useful in medical and a range of other sensing, memory and logic applications. This book introduces the theoretical foundations and practical realization of devices in organic electronics. It is a product of both one and two semester courses that have been taught over a period of more than two decades. The target audiences are students at all levels of graduate studies, highly motivated senior undergraduates, and practicing engineers and scientists. The book is divided into two sections. Part I, Foundations, lays down the fundamental principles of the field of organic electronics. It is assumed that the reader has an elementary knowledge of quantum mechanics, and electricity and magnetism. Background knowledge of organic chemistry is not required. Part II, Applications, focuses on organic electronic devices. It begins with a discussion of organic thin film deposition and patterning, followed by chapters on organic light emitters, detectors, and thin film transistors. The last chapter describes several devices and phenomena that are not covered in the previous chapters, since they lie outside of the current mainstream of the field, but are nevertheless important.Less
Organic electronics is a platform for very low cost and high performance optoelectronic and electronic devices that cover large areas, are lightweight, and can be both flexible and conformable to irregularly shaped surfaces such as foldable smart phones. Organics are at the core of the global organic light emitting device (OLED) display industry, and also having use in efficient lighting sources, solar cells, and thin film transistors useful in medical and a range of other sensing, memory and logic applications. This book introduces the theoretical foundations and practical realization of devices in organic electronics. It is a product of both one and two semester courses that have been taught over a period of more than two decades. The target audiences are students at all levels of graduate studies, highly motivated senior undergraduates, and practicing engineers and scientists. The book is divided into two sections. Part I, Foundations, lays down the fundamental principles of the field of organic electronics. It is assumed that the reader has an elementary knowledge of quantum mechanics, and electricity and magnetism. Background knowledge of organic chemistry is not required. Part II, Applications, focuses on organic electronic devices. It begins with a discussion of organic thin film deposition and patterning, followed by chapters on organic light emitters, detectors, and thin film transistors. The last chapter describes several devices and phenomena that are not covered in the previous chapters, since they lie outside of the current mainstream of the field, but are nevertheless important.
Bob Aveyard
- Published in print:
- 2019
- Published Online:
- December 2019
- ISBN:
- 9780198828600
- eISBN:
- 9780191867125
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198828600.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials, Soft Matter / Biological Physics
Characteristically, surfactants in aqueous solution adsorb at interfaces and form aggregates (micelles of various shapes and sizes, microemulsion droplets, and lyotropic liquid crystalline phases). ...
More
Characteristically, surfactants in aqueous solution adsorb at interfaces and form aggregates (micelles of various shapes and sizes, microemulsion droplets, and lyotropic liquid crystalline phases). This book is about the behaviour of surfactants in solution, at interfaces, and in colloidal dispersions. Adsorption at liquid/fluid and solid/liquid interfaces, and ways of characterizing the adsorbed surfactant films, are explained. Surfactant aggregation in systems containing only an aqueous phase and in systems with comparable volumes of water and nonpolar oil are each considered. In the latter case, the surfactant distribution between oil and water and the behaviour of the resulting Winsor systems are central to surfactant science and to an understanding of the formation of emulsions and microemulsions. Surfactant layers on particle or droplet surfaces can confer stability on dispersions including emulsions, foams, and particulate dispersions. The stability is dependent on the surface forces between droplet or particle surfaces and the way in which they change with particle separation. Surface forces are also implicated in wetting processes and thin liquid film formation and stability. The rheology of adsorbed films on liquids and of bulk colloidal dispersions is covered in two chapters. Like surfactant molecules, small solid particles can adsorb at liquid/fluid interfaces and the final two chapters focus on particle adsorption, the behaviour of adsorbed particle films and the stabilization of Pickering emulsions.Less
Characteristically, surfactants in aqueous solution adsorb at interfaces and form aggregates (micelles of various shapes and sizes, microemulsion droplets, and lyotropic liquid crystalline phases). This book is about the behaviour of surfactants in solution, at interfaces, and in colloidal dispersions. Adsorption at liquid/fluid and solid/liquid interfaces, and ways of characterizing the adsorbed surfactant films, are explained. Surfactant aggregation in systems containing only an aqueous phase and in systems with comparable volumes of water and nonpolar oil are each considered. In the latter case, the surfactant distribution between oil and water and the behaviour of the resulting Winsor systems are central to surfactant science and to an understanding of the formation of emulsions and microemulsions. Surfactant layers on particle or droplet surfaces can confer stability on dispersions including emulsions, foams, and particulate dispersions. The stability is dependent on the surface forces between droplet or particle surfaces and the way in which they change with particle separation. Surface forces are also implicated in wetting processes and thin liquid film formation and stability. The rheology of adsorbed films on liquids and of bulk colloidal dispersions is covered in two chapters. Like surfactant molecules, small solid particles can adsorb at liquid/fluid interfaces and the final two chapters focus on particle adsorption, the behaviour of adsorbed particle films and the stabilization of Pickering emulsions.
Kannan M. Krishnan
- Published in print:
- 2016
- Published Online:
- December 2016
- ISBN:
- 9780199570447
- eISBN:
- 9780191813504
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199570447.003.0007
- Subject:
- Physics, Condensed Matter Physics / Materials
In this chapter we introduce the relevant energy terms to determine the formation of domains. The regions of transition separating one domain from the next are classified as Bloch, Néel, or cross-tie ...
More
In this chapter we introduce the relevant energy terms to determine the formation of domains. The regions of transition separating one domain from the next are classified as Bloch, Néel, or cross-tie domain walls. We then analyze domain structures based on energy considerations and demonstrate their utility for simple structures such as particle and films. However, every domain configuration is one of many possible metastable states and which one is realized in practice depends on the magnetization history. The Stoner–Wohlfarth (S–W) coherent rotation model describes the magnetization reversal and hysteresis of an ensemble of small particles. This model, which shows that their coercive field is ideally equal to the anisotropy field, has great practical utility and is discussed further in §9 and §11. Two effective approaches to understanding the process of magnetization and its reversal are coherent rotation and alternatively, a simple potential energy approximation involving the movement, pinning, and de-pinning of domain walls. Finally, the magnetization behavior as a function of the magnetic field, has a simple functional form at both low and high field values. Broadly, domains are expected in the size range 1 nm−10 μm. Techniques for observing and modeling them are discussed in the next chapter.Less
In this chapter we introduce the relevant energy terms to determine the formation of domains. The regions of transition separating one domain from the next are classified as Bloch, Néel, or cross-tie domain walls. We then analyze domain structures based on energy considerations and demonstrate their utility for simple structures such as particle and films. However, every domain configuration is one of many possible metastable states and which one is realized in practice depends on the magnetization history. The Stoner–Wohlfarth (S–W) coherent rotation model describes the magnetization reversal and hysteresis of an ensemble of small particles. This model, which shows that their coercive field is ideally equal to the anisotropy field, has great practical utility and is discussed further in §9 and §11. Two effective approaches to understanding the process of magnetization and its reversal are coherent rotation and alternatively, a simple potential energy approximation involving the movement, pinning, and de-pinning of domain walls. Finally, the magnetization behavior as a function of the magnetic field, has a simple functional form at both low and high field values. Broadly, domains are expected in the size range 1 nm−10 μm. Techniques for observing and modeling them are discussed in the next chapter.