The properties of hot electrons in systems where electrons and phonons experience quantum confinement are reviewed. The modifications to the behaviour of electrons and phonons brought about by confinement are described, particularly with reference to the principal scattering mechanism. The latter include the interaction with longitudinal optical phonons and plasmons, along with carrier-carrier effects. Some conflict in the literature concerning Fuchs-Kliewer polaritons is discussed. Low-temperature interactions with acoustic phonons are described. A central topic is that of energy relaxation, and the experimental and theoretical data relating to this form a large part of the review. Energy relaxation mechanisms in the femtosecond to nanosecond regimes, including intersubband and well-capture processes, are eventually summarized. An equally large section deals with hot-electron transport; in which negative differential resistance and other instabilities associated with parallel transport are discussed before turning to ballistic transport and impact ionization.

https://iopscience.iop.org/article/10.1088/0034-4885/54/2/001/pdf

Hot electrons in low-dimensional structures

The properties of charge carriers in solids can be modified greatly by their real and virtual interactions with optical phonons. These effects differ in two particular ways from the changes induced by interactions with acoustic lattice modes. Firstly, those optical modes which interact with carriers are closely monochromatic. Sharply defined structure can therefore appear in many experimental observations, including optical properties, photoconductivity, tunnelling, the magnetoresistance observed under quantum-limit conditions and a range of coupled mode phenomena embracing boht single carriers and plasma modes. Secondly, in materials of a polar nature the coupling of carriers to the optical modes is particularly strong and the resulting scattering probabilities and changes in effective mass can be large. Nevertheless, significant effects produced by the optical modes may be observed in homopolar semiconductors such as silicon and germanium. This article reviews the consequences of the coupling between the carriers and the optical phonons. The theory of such interactions is developed at length and then applied to a wide range of experimental observations in semiconducting and in insulating solids.

https://iopscience.iop.org/article/10.1088/0034-4885/36/1/001/pdf

Electrons and optic phonons in solids-the effects of longitudinal optical lattice vibrations on the electronic excitations of solids

Surface quantum states in tellurium

Far-infrared photoconductivity from the shallow donors in n-InP

A critical review is given of recent experimental and quantum transport theoretical studies of hot electrons in quantizing magnetic fields. Particular attention is paid to new effective temperature models and to numerical solutions to exact quantum kinetic equations. The latter are discussed within a unified framework based on resolvent analyses of the Liouville equation. Special emphasis is given to carrier-carrier scattering, non-parabolicity, resonance phenomena and non-heating non-linear departures from Ohm's law. The optical determination of quantum distributions and the application of Fourier transform and harmonic detection techniques to hot carrier magneto-resonance spectroscopy is discussed with emphasis on magnetophonon and magnetic-impurity phenomena.

Hot electron quantum magneto-transport

The magnetoresistance of three samples of high purity n-type insb(nd-na varying from 5*1013 to 5*1014 cm-3) is studied at lattice temperatures of 11 and 20 k with electric field strengths sufficient (>100 mv cm-1) to heat the electron distribution appreciably above the temperature of the lattice and at magnetic field strengths such that the effect of landau quantization is apparent. Two distinct types of magnetophonon extrema are observed, each having a different dependence on electric field and temperature. The first consists of a series of minima which are only observed when the electron temperature is in excess of about 20 k and which arises from the emission of long wavelength longitudinal optical (lo) phonons.

https://iopscience.iop.org/article/10.1088/0022-3719/3/12/007/pdf

R A Stradling

Papers

The application of the magnetophonon effect to a study of hot electron phenomena in insb