Lawrence Challis (ed.)
- Published in print:
- 2003
- Published Online:
- January 2010
- ISBN:
- 9780198507321
- eISBN:
- 9780191709319
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507321.001.0001
- Subject:
- Physics, Atomic, Laser, and Optical Physics
The study of electrons and holes confined to two, one, and even zero dimensions has uncovered a rich variety of new physics and applications. This book describes the interaction between these ...
More
The study of electrons and holes confined to two, one, and even zero dimensions has uncovered a rich variety of new physics and applications. This book describes the interaction between these confined carriers and the optic and acoustic phonons within and around the confined regions. Phonons provide the principal channel of energy transfer between the carriers and their surroundings and also the main restriction to their room temperature mobility. However, they also have many other roles; they contribute, for example, an essential feature to the operation of the quantum cascade laser. Since their momenta at relevant energies are well matched to those of electrons, they can also be used to probe electronic properties such as the confinement width of two-dimensional (2-D) electron gases and the dispersion curve of quasiparticles in the fractional quantum Hall effect. The book describes both the physics of the electron-phonon interaction in the different confined systems and the experimental and theoretical techniques that have been used in its investigation. The experimental methods include optical and transport techniques as well as techniques in which phonons are used as the experimental probe. This book provides an up-to-date review of the physics and its significance in device performance.Less
The study of electrons and holes confined to two, one, and even zero dimensions has uncovered a rich variety of new physics and applications. This book describes the interaction between these confined carriers and the optic and acoustic phonons within and around the confined regions. Phonons provide the principal channel of energy transfer between the carriers and their surroundings and also the main restriction to their room temperature mobility. However, they also have many other roles; they contribute, for example, an essential feature to the operation of the quantum cascade laser. Since their momenta at relevant energies are well matched to those of electrons, they can also be used to probe electronic properties such as the confinement width of two-dimensional (2-D) electron gases and the dispersion curve of quasiparticles in the fractional quantum Hall effect. The book describes both the physics of the electron-phonon interaction in the different confined systems and the experimental and theoretical techniques that have been used in its investigation. The experimental methods include optical and transport techniques as well as techniques in which phonons are used as the experimental probe. This book provides an up-to-date review of the physics and its significance in device performance.
Lucjan Jacak, Piotr Sitko, Konrad Wieczorek, and Arkadiusz Wójs
- Published in print:
- 2003
- Published Online:
- January 2010
- ISBN:
- 9780198528708
- eISBN:
- 9780191713477
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198528708.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials, Theoretical, Computational, and Statistical Physics
The book presents the wide range of topics in two-dimensional physics of quantum Hall systems, especially fractional quantum Hall states. It starts with the fundamental problems of quantum statistics ...
More
The book presents the wide range of topics in two-dimensional physics of quantum Hall systems, especially fractional quantum Hall states. It starts with the fundamental problems of quantum statistics in two dimensions and the corresponding braid group formalism. The braid group formalism of anyons (previously known) is developed for composite fermions. The effective formalism used in many-body quantum Hall theories — the Chern–Simons theory is also presented. The Chern–Simons theory of anyons (particles obeying fractional statistics) and composite fermions (related to Hall systems) is given, in detail. Numerical studies, which play the important role in quantum Hall analyses, are presented for spherical systems (Haldane sphere). The composite fermion theory is tested in numerical studies. The concept of the hierarchy of condensed states of composite fermion excitations is introduced (in analogy to the Haldane hierarchy). The hierarchies of odd-denominator states and even-denominator states are presented. The BCS paired Hall state is also discussed. An introduction to multi-component quantum Hall systems and spin quantum Hall systems is sketched.Less
The book presents the wide range of topics in two-dimensional physics of quantum Hall systems, especially fractional quantum Hall states. It starts with the fundamental problems of quantum statistics in two dimensions and the corresponding braid group formalism. The braid group formalism of anyons (previously known) is developed for composite fermions. The effective formalism used in many-body quantum Hall theories — the Chern–Simons theory is also presented. The Chern–Simons theory of anyons (particles obeying fractional statistics) and composite fermions (related to Hall systems) is given, in detail. Numerical studies, which play the important role in quantum Hall analyses, are presented for spherical systems (Haldane sphere). The composite fermion theory is tested in numerical studies. The concept of the hierarchy of condensed states of composite fermion excitations is introduced (in analogy to the Haldane hierarchy). The hierarchies of odd-denominator states and even-denominator states are presented. The BCS paired Hall state is also discussed. An introduction to multi-component quantum Hall systems and spin quantum Hall systems is sketched.
C.J. Mellor, W. Dietsche, and L.J. Challis
- Published in print:
- 2003
- Published Online:
- January 2010
- ISBN:
- 9780198507321
- eISBN:
- 9780191709319
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507321.003.0003
- Subject:
- Physics, Atomic, Laser, and Optical Physics
This chapter describes investigations of the interaction of phonons with magnetically quantized two-dimensional (2-D) electron systems including the quantum Hall states, with particular attention to ...
More
This chapter describes investigations of the interaction of phonons with magnetically quantized two-dimensional (2-D) electron systems including the quantum Hall states, with particular attention to work using acoustic phonons as probes. This includes studies of phonon emission from the two diagonally opposite ‘hot spots’ of a Hall bar where the current enters and leaves. One study detected the phonons using bolometers placed opposite the corners and, in another, the temperature increases at the ‘hot spots’ were indicated by the thickness of superfluid helium film covering the Hall bar. Information has also been obtained on the frequency spectrum of the emitted phonons. Studies have been made of the location and frequency dependence of the absorption of phonons in the integer states. Phonon absorption studies of the fractional quantum Hall state provide support for the magnetoroton picture, and the fruitful studies of the quantum Hall states using surface acoustic waves are reviewed in detail.Less
This chapter describes investigations of the interaction of phonons with magnetically quantized two-dimensional (2-D) electron systems including the quantum Hall states, with particular attention to work using acoustic phonons as probes. This includes studies of phonon emission from the two diagonally opposite ‘hot spots’ of a Hall bar where the current enters and leaves. One study detected the phonons using bolometers placed opposite the corners and, in another, the temperature increases at the ‘hot spots’ were indicated by the thickness of superfluid helium film covering the Hall bar. Information has also been obtained on the frequency spectrum of the emitted phonons. Studies have been made of the location and frequency dependence of the absorption of phonons in the integer states. Phonon absorption studies of the fractional quantum Hall state provide support for the magnetoroton picture, and the fruitful studies of the quantum Hall states using surface acoustic waves are reviewed in detail.
L.J. Challis
- Published in print:
- 2003
- Published Online:
- January 2010
- ISBN:
- 9780198507321
- eISBN:
- 9780191709319
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507321.003.0001
- Subject:
- Physics, Atomic, Laser, and Optical Physics
While the physics of low-dimensional structures mainly involves their electronic properties, an understanding of the interaction between the electrons and holes and the phonons present within and ...
More
While the physics of low-dimensional structures mainly involves their electronic properties, an understanding of the interaction between the electrons and holes and the phonons present within and around the confined layers is frequently needed if this physics is to be understood in detail. This introductory chapter gives examples of this and outlines the experimental methods that have been used to study the electron-phonon interactions. These include both optical and transport techniques and also techniques that involve the use of phonons as probes: phonon techniques. Phonons interact much more strongly with electrons than photons of the same frequency since their momenta are usually much closer to those of the confined electrons, and phonon techniques have been used to obtain information ranging from the confinement widths to the dispersion curve of quasiparticles in the fractional quantum Hall state.Less
While the physics of low-dimensional structures mainly involves their electronic properties, an understanding of the interaction between the electrons and holes and the phonons present within and around the confined layers is frequently needed if this physics is to be understood in detail. This introductory chapter gives examples of this and outlines the experimental methods that have been used to study the electron-phonon interactions. These include both optical and transport techniques and also techniques that involve the use of phonons as probes: phonon techniques. Phonons interact much more strongly with electrons than photons of the same frequency since their momenta are usually much closer to those of the confined electrons, and phonon techniques have been used to obtain information ranging from the confinement widths to the dispersion curve of quasiparticles in the fractional quantum Hall state.
