We present a comprehensive, up-to-date compilation of band parameters for the technologically important III–V zinc blende and wurtzite compound semiconductors: GaAs, GaSb, GaP, GaN, AlAs, AlSb, AlP, AlN, InAs, InSb, InP, and InN, along with their ternary and quaternary alloys. Based on a review of the existing literature, complete and consistent parameter sets are given for all materials. Emphasizing the quantities required for band structure calculations, we tabulate the direct and indirect energy gaps, spin-orbit, and crystal-field splittings, alloy bowing parameters, effective masses for electrons, heavy, light, and split-off holes, Luttinger parameters, interband momentum matrix elements, and deformation potentials, including temperature and alloy-composition dependences where available. Heterostructure band offsets are also given, on an absolute scale that allows any material to be aligned relative to any other.

Band parameters for III–V compound semiconductors and their alloys

A topological insulator has surface metallic states that are topologically protected by time-reversal symmetry. Tin telluride is now shown to be a ‘topological crystalline insulator’, in which the surface metallic state is instead protected by the mirror symmetry of the crystal.

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Experimental realization of a topological crystalline insulator in SnTe

Publisher Summary This chapter reviews the thermal conductivity of nonmetallic crystals at temperatures comparable to or higher than the Debye temperature. It deals with the intrinsic behavior of such pure crystals at high temperatures. In such crystals, the dominant carriers of thermal energy are phonons and the dominant scattering mechanism to be considered is the intrinsic phonon–phonon scattering. This is a small section of the much larger problem of the thermal conductivity of nonmetallic solids and clearly it neglects possible heat transport by photons, charge carriers, polarons, and magnons. It also neglects other possible phonon scattering mechanisms such as isotopes, impurities, vacancies, charge carriers, dislocations, grain boundaries, and crystal boundaries. It presents the absolute value of the thermal conductivity, K, as determined by phonon–phonon scattering, the temperature dependence of K, the volume dependence of K, the change in K upon melting, and the minimum value of K. The chapter discusses a composite curve for the thermal conductivity versus temperature of pure KCl measured at a constant pressure of, say, one atmosphere.

The Thermal Conductivity of Nonmetallic Crystals

Various models for calculation of physical parameters in compound alloys are discussed and the results for In1−x Gax Asy P1−y quaternaries are presented. The model used is based on a linear interpolation scheme, and therefore necessitates known values of the parameters for the related binary and ternary alloys. The material parameters considered in the present study can be classified into the following eleven groups: (1) lattice constant and crystal density, (2) thermal expansion coefficient, (3) electronic‐band structure, (4) external perturbation effect on the lowest‐direct gap, (5) effective mass, (6) dielectric constant, (7) Frohlich coupling parameter, (8) elastic properties, (9) piezoelectric properties, (10) deformation potential, and (11) excitonic effect. Of particular interest is the deviation of material parameters from linearity with respect to the alloy composition. It is found that the present model provides generally acceptable parameters, in good agreement with the existing experimental da...

Material parameters of In1−xGaxAsyP1−y and related binaries

Several materials have been identified over the past few years as promising candidates for the development of new generations of magnetoresistive devices. These range from artificially engineered magnetic multilayers' and granular alloys, in which the magnetic-field response of interfacial spins modulates electron transport to give rise to 'giant' magnetoresistance, to the manganite peravskites, in which metal-insulator transitions driven by a magnetic field give rise to a `colossal' magnetoresistive response (albeit at very high fields). Here we describe a hitherto unexplored class of magnetoresistive compounds, the silver chalcogenides. At high temperatures, the compounds Ag_2S, Ag_2Se and Ag_2Te are superionic conductors; below similar to 400 K, ion migration is effectively frozen and the compounds are non-magnetic semiconductors that exhibit no appreciable magnetoresistance. We show that slightly altering the stoichiometry can lead to a marked increase in the magnetic response. At room temperature and in a magnetic field of similar to 55 kOe, Ag_(2+δ)Se and Ag_(2+δ)Te show resistance increases of up to 200%, which are comparable with the colossal-magnetoresistance materials. Moreover, the resistance of our most responsive samples exhibits an unusual linear dependence on magnetic field, indicating both a potentially useful response down to fields of practical importance and a peculiarly long length scale associated with the underlying mechanism.

Large magnetoresistance in non-magnetic silver chalcogenides

Measurements of the elastic constants and thermal expansion of PbTe have been made from 4.2° to 303.2°K. The extrapolated 0°K values for C44, (C11−C12)/2, and (C11+2C12)/3, respectively, are 1.514±0.009, 6.184±0.066, and 4.560±0.042×1011 dyn/cm2. At 303.2°K these values are 1.344±0.008, 5.016±0.057, and 4.107±0.037×1011 dyn/cm2. Intermediate values are presented graphically, as are the thermal‐expansion data. The linear coefficient of thermal expansion is found to be 20.4±0.4×10−6/°C at room temperature. The 0°K Debye temperature is calculated to be 176.7°±0.5°K.

Elastic Constants, Thermal Expansion, and Debye Temperature of Lead Telluride

Weak-field magnetoresistance measurements on $p$-type SnTe exhibit a peculiar symmetry which is temperature and carrier-concentration dependent. A Fermi-surface model is described which can account for these results and reconcile them with several other kinds of experimental measurements on SnTe. The Fermi surface consists of four prolate $〈111〉$ valleys with three $〈100〉$-oriented knobs protruding from each end of each valley. The proposed model is also used to bring out some previously unreported similarities between the band structures of the ${\mathrm{Pb}}_{1\ensuremath{-}x}{\mathrm{Sn}}_{x}\mathrm{Te}$ and ${\mathrm{Bi}}_{1\ensuremath{-}x}{\mathrm{Sb}}_{x}$ systems, and to examine the broader question of the connection between weak-field magnetoresistance behavior and band-structure characteristics.

Weak-Field Magnetoresistance and the Valence-Band Structure of SnTe

We have studied the angular dependence of Shubnikov-de Haas oscillations in a sample of $p$-type PbTe having a hole concentration of 3.0 \ifmmode\times\else\texttimes\fi{} ${10}^{18}$ ${\mathrm{cm}}^{\ensuremath{-}3}$. Orientations of the magnetic field in a {110} plane and temperatures between 4.2 and 1.2\ifmmode^\circ\else\textdegree\fi{}K were used. For the first time in this material, the component frequencies were determined by Fourier analysis. The angular dependence of the corresponding extremal areas was precisely fitted by four $〈111〉$-oriented ellipsoids of revolution having a "mass anisotropy" of 13 and containing the same number of holes as that determined from the high-field Hall coefficient. These results, which are considerably different from those previously reported by Cuff et al. for material with the same hole concentration, suggest that the anisotropy is constant, at least up to the hole concentration studied here. A $\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{\ensuremath{\rightarrow}}{\mathrm{p}}$ band model, consistent with this behavior and with other results presented here, is considered. From the temperature dependence of the oscillations with $\stackrel{\ensuremath{\rightarrow}}{\mathrm{H}}\ensuremath{\parallel}[111]$, the transverse effective mass at the Fermi level ${m}_{\ensuremath{\perp}}({\ensuremath{\epsilon}}_{F})$ is $(0.036\ifmmode\pm\else\textpm\fi{}0.002)m$. Longitudinal and transverse effective $g$ values at the Fermi level were determined from the spin splitting of peaks in the oscillations. For $\stackrel{\ensuremath{\rightarrow}}{\mathrm{H}}\ensuremath{\parallel}[111]$, the ratio of spin splitting to Landau-level separation is 0.58 \ifmmode\pm\else\textpm\fi{} 0.01, and ${g}_{\ensuremath{\parallel}}({\ensuremath{\epsilon}}_{F})=32\ifmmode\pm\else\textpm\fi{}2$. For ${\stackrel{\ensuremath{\rightarrow}}{\mathrm{H}}}_{\ensuremath{\perp}}[111]$, this ratio is 0.27 \ifmmode\pm\else\textpm\fi{} 0.01, and ${g}_{\ensuremath{\perp}}({\ensuremath{\epsilon}}_{F})=7\ifmmode\pm\else\textpm\fi{}2$.

Anisotropy of the Fermi Surface of p-Type PbTe

We have used the de Haas-van Alphen effect and Shubnikov---de Haas effect at temperatures from 1.6 to 7.9 K to investigate the Fermi surface of SnTe. Nine samples were studied covering a range in carrier concentration from 5 \ifmmode\times\else\texttimes\fi{} ${10}^{19}$ to 5 \ifmmode\times\else\texttimes\fi{} ${10}^{20}$ ${\mathrm{cm}}^{\ensuremath{-}3}$. The nature of the data is such that they divide into two regions in carrier concentration, a normal one at or above 3.6 \ifmmode\times\else\texttimes\fi{} ${10}^{20}$ ${\mathrm{cm}}^{\ensuremath{-}3}$ and an anomalous one at or below 2.1 \ifmmode\times\else\texttimes\fi{} ${10}^{20}$ ${\mathrm{cm}}^{\ensuremath{-}3}$. In the normal region one extremal cross section was observed at each orientation describing a pocket elongated in a $〈111〉$ direction and located at the $L$ point. In addition, oscillations describing a second set of pockets elongated in a $〈100〉$ direction were observed. At a carrier concentration of 3.6 \ifmmode\times\else\texttimes\fi{} ${10}^{20}$ ${\mathrm{cm}}^{\ensuremath{-}3}$, Dingle temperatures and cyclotron masses of 21.6 K and $0.125{m}_{0}$ and 17.3 K and $0.094{m}_{0}$ were measured for the $〈111〉$ and $〈100〉$ pockets, respectively. At about this carrier concentration a density of states of 6 \ifmmode\times\else\texttimes\fi{} ${10}^{21}$ ${(\mathrm{e}\mathrm{V}\phantom{\rule{0ex}{0ex}}{\mathrm{cm}}^{3})}^{\ensuremath{-}1}$ was computed from the data and is in fair agreement with the density of states computed from heat-capacity measurements. In the anomalous region a number of extremal cross sections describing one pocket at the $L$ point were observed at each orientation. The shapes of the constant-energy surfaces described by the data are in poor agreement with the results of existing band calculations.

Bland Houston

Papers

Elastic Constants, Thermal Expansion, and Debye Temperature of Lead Telluride

Weak-Field Magnetoresistance and the Valence-Band Structure of SnTe

Anisotropy of the Fermi Surface of p-Type PbTe

FERMI SURFACE STUDIES IN SnTe.

Fermi-surface parameters of p-type PbTe as a function of carrier density