Electron Spectrum of Gapless Semiconductors

Electron Spectrum of Gapless Semiconductors presents the peculiarities of physical properties of a comparatively new class of solids - gapless semiconductors (GS). These peculiarities are determined by the main feature of the elctron spectrum, namely the absence of a gap between the conduction and valence bands. GSs form a boundary between metals and semiconductors. On the other hand GSs are of practical interest since they are very sensitive to impurities, and to the influence of light, magnetic and electric fields, and pressure.

Klappentext

Electron Spectrum of Gapless Semiconductors presents the peculiarities of physical properties of a comparatively new class of solids - gapless semiconductors (GS). These peculiarities are determined by the main feature of the elctron spectrum, namely the absence of a gap between the conduction and valence bands. GSs form a boundary between metals and semiconductors. On the other hand GSs are of practical interest since they are very sensitive to impurities, and to the influence of light, magnetic and electric fields, and pressure.

Inhalt

1. Introduction.- 2. Band-Structure Calculation Methods.- 2.1 Adiabatic Approximation.- 2.2 The One-Electron Hartree-Fock Approximation.- 2.3 Correlation Phenomena.- 2.4 Methods Used to Solve the Schrödinger Equation.- 3. Insulators, Semiconductors, Metals.- 3.1 The Detection of the Gapless State.- 3.2 Gray Tin.- 3.3 Mercury Chalcogenides HgTe and HgSe.- 4. Impurities.- 4.1 The Problem of Residual Electron Concentration.- 4.2 Impurities and Intrinsic Defects in Mercury Chalcogenides..- 4.3 Energies of Impurity States.- 4.4 Metal-Insulator Transitions.- 4.5 The Mott Transition in n-Type Crystals.- 4.6 The Influence of Compensation on the Mott Transition.- 4.7 An "Anomaly" in the Temperature Dependence of the Electron Concentration.- 4.8 Freeze-Out of Electrons onto Acceptors in a Magnetic Field.- 4.9 Freeze-Out of Electrons onto Acceptors Subject to Hydrostatic Pressure.- 4.10 On the Mobility of Holes in Gapless HgCdTe Crystals.- 5. Semimagnetic Semiconductors.- 5.1 HgMnTe Crystals.- 5.2 HgSe:Fe Crystals.- 5.4 DX Centers.- 5.5 The Improved Short-Range Correlation Model.- 6. Conclusion.- 6.1 Practical Applications of Gapless Semiconductors.- 6.2 Some Results and Problems.- References.