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Journal ArticleDOI

On the thermoelectric power in n-channel inversion layers of ternary chalcopyrite semiconductors under magnetic quantization

01 Jul 1991-Journal of Applied Physics (American Institute of Physics)-Vol. 70, Iss: 1, pp 299-304
TL;DR: In this paper, an attempt is made to investigate the thermoelectric power of the electrons under strong magnetic quantization in n-channel inversion layers of ternary chalcopyrite semiconductors at low temperatures, taking n−channel inversions layers on CdGeAs2 as examples, under both the weak and strong electric field limits, respectively.
Abstract: An attempt is made to investigate the thermoelectric power of the electrons under strong magnetic quantization in n‐channel inversion layers of ternary chalcopyrite semiconductors at low temperatures, taking n‐channel inversion layers on CdGeAs2 as examples, under both the weak and strong electric field limits, respectively. We have formulated the magneto‐thermo power on the basis of newly derived two‐dimensional electron energy spectra for both the limits by considering various types of anisotropies of the band parameters within the frame work of k■p formalism. It has been observed that, the magneto‐thermo power decreases with increasing surface electric field and decreasing quantizing magnetic field in an oscillatory manner for both the limits. The crystal field parameter enhances the numerical magnitudes and the corresponding results for n‐channel inversion layers of parabolic semiconductors have also been obtained as special cases from the generalized expressions under certain limiting conditions.
Citations
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Book ChapterDOI
TL;DR: In this article, the structure, magnetic, and related properties of the ThMn12-type compounds of rare earths and actinides are presented, and the magnetic coupling for these compounds is determined only for the AnFe4Al8 seiles in neutron diffraction (ND) experiment.
Abstract: Publisher Summary This chapter presents the structure, magnetic, and related properties of the ThMn12-type compounds of rare earths and actinides. There are two distinct subgroups in this family of compounds: (1) those with a relatively low content of transition element and (2) those with a high concentration of the iron-group elements, mostly Fe, Co, and Ni. For the first subgroup, the transition elements belong to the iron group except for Co and Ni and the most popular stabilizing element is Al; however, Ga can also be used as a stabilizing component. For the second subgroup, Si, Ti, V, Cr, Mn, Mo, and Re are most frequently found as the stabilizing component for the rare-earth compounds, whereas only compounds with Si, and exceptionally with Mo and Re, are formed by uranium. The magnetic coupling for the ThMn12-type compounds is determined only for the AnFe4Al8 seiles in neutron diffraction (ND) experiment. Neutron investigations have been performed for other compounds as well, although for these either the transition-metal sublattice or both the actinide and transition-metal sublattices are nonmagnetic.

26 citations

Journal ArticleDOI
TL;DR: In this paper, the thermoelectric power in the presence of a large magnetic field (TPM) in heavily doped III-V, II-VI, PbTe/PbSnTe, strained layer and HgTe/CdTe quantum dot superlattices (QDSLs) with graded structures was analyzed.
Abstract: We study theoretically the thermoelectric power in the presence of a large magnetic field (TPM) in heavily doped III–V, II–VI, PbTe/PbSnTe, strained layer and HgTe/CdTe quantum dot superlattices (QDSLs) with graded structures on the basis of newly formulated electron energy spectra and compare the same with that of the constituent materials. It has been found, taking heavily doped GaAs/Ga1−xAlxAs, CdS/CdTe, PbTe/PbSnTe, InAs/GaSb and HgTe/CdTe QDSLs as examples, that the TPM increases with increasing inverse electron concentration and film thickness, respectively, in different oscillatory manners and the nature of oscillations is totally band structure dependent. We have also suggested the experimental methods of determining the Einstein relation for the diffusivity–mobility ratio, the Debye screening length and the electronic contribution to the elastic constants for materials having arbitrary dispersion laws.

23 citations

Journal ArticleDOI
TL;DR: In this paper, a simple theoretical analysis of the thermoelectric power under strong magnetic quantization (TPM) in III-V, II-VI, PbTe/PbSnTe, strained layer and HgTe/CdTe superlattices (SLs) with graded interfaces was presented.
Abstract: An attempt is made in this paper to present a simple theoretical analysis of the thermoelectric power under strong magnetic quantization (TPM) in III–V, II–VI, PbTe/PbSnTe, strained layer and HgTe/CdTe superlattices (SLs) with graded interfaces and compare the same with that of the constituent materials by formulating the respective magneto dispersion laws, which in turn control all the transport properties through Bolzmann transport equation. It has been observed, taking GaAs/Ga 1− x Al x As, CdS/CdTe, PbTe/PbSnTe, InAs/GaSb and HgTe/CdTe with graded interfaces as examples, that the TPM exhibits oscillatory dependence with the inverse quantizing magnetic field due to the SdH and allied SL effects and increases with increasing inverse electron concentration in an oscillatory manner in all the cases. The nature of oscillation is totally band structure dependent and the width of the finite interface enhances the numerical values of the TPM for all the aforementioned SLs. The numerical values of the TPM in graded SLs are greater than that of the constituent materials. The theoretical results are in quantitative agreement with the experimental results as given elsewhere. The well-known expressions for the bulk specimens of wide-gap materials can also be obtained as special cases of our generalized analysis under certain limiting conditions. In addition, we have suggested the experimental methods of determining the Einstein relation for diffusivity–mobility ratio, the Debye screening length and carrier contribution to the elastic constants, respectively, for materials having arbitrary dispersion laws.

19 citations

Journal ArticleDOI
TL;DR: In this paper, the authors studied thermoelectric power under strong magnetic field (TPM) in carbon nanotubes (CNTs) and quantum wires (QWs) of nonlinear optical, optoelectronic, and related materials.
Abstract: We study thermoelectric power under strong magnetic field (TPM) in carbon nanotubes (CNTs) and quantum wires (QWs) of nonlinear optical, optoelectronic, and related materials. The corresponding results for QWs of III-V, ternary, and quaternary compounds form a special case of our generalized analysis. The TPM has also been investigated in QWs of II-VI, IV-VI, stressed materials, n-GaP, p-PtSb2, n-GaSb, and bismuth on the basis of the appropriate carrier dispersion laws in the respective cases. It has been found, taking QWs of n-CdGeAs2, n-Cd3As2, n-InAs, n-InSb, n-GaAs, n-Hg1?xCdxTe, n-In1?xGaxAsyP1?y lattice-matched to InP, p-CdS, n-PbTe, n-PbSnTe, n-Pb1?xSnxSe, stressed n-InSb, n-GaP, p-PtSb2, n-GaSb, and bismuth as examples, that the respective TPM in the QWs of the aforementioned materials exhibits increasing quantum steps with the decreasing electron statistics with different numerical values, and the nature of the variations are totally band-structure-dependent. In CNTs, the TPM exhibits periodic oscillations with decreasing amplitudes for increasing electron statistics, and its nature is radically different as compared with the corresponding TPM of QWs since they depend exclusively on the respective band structures emphasizing the different signatures of the two entirely different one-dimensional nanostructured systems in various cases. The well-known expression of the TPM for wide gap materials has been obtained as a special case under certain limiting conditions, and this compatibility is an indirect test for our generalized formalism. In addition, we have suggested the experimental methods of determining the Einstein relation for the diffusivity-mobility ratio and the carrier contribution to the elastic constants for materials having arbitrary dispersion laws.

17 citations

Journal ArticleDOI
TL;DR: In this article, the influence of light waves on the thermoelectric power under large magnetic field (TPM) for III-V, ternary and quaternary materials, whose unperturbed energy-band structures, are defined by the three-band model of Kane.
Abstract: We study theoretically the influence of light waves on the thermoelectric power under large magnetic field (TPM) for III-V, ternary and quaternary materials, whose unperturbed energy-band structures, are defined by the three-band model of Kane. The solution of the Boltzmann transport equation on the basis of this newly formulated electron dispersion law will introduce new physical ideas and experimental findings in the presence of external photoexcitation. It has been found by taking n-InAs, n-InSb, n-Hg1-xCdxTe and n-In1-xGaxAsyP1-y lattice matched to InP as examples that the TPM decreases with increase in electron concentration, and increases with increase in intensity and wavelength, respectively in various manners. The strong dependence of the TPM on both light intensity and wavelength reflects the direct signature of light waves that is in direct contrast as compared with the corresponding bulk specimens of the said materials in the absence of external photoexcitation. The rate of change is totally band-structure dependent and is significantly influenced by the presence of the different energy-band constants. The well-known result for the TPM for nondegenerate wide-gap materials in the absence of light waves has been obtained as a special case of the present analysis under certain limiting conditions and this compatibility is the indirect test of our generalized formalism. Besides, we have also suggested the experimental methods of determining the Einstein relation for the diffusivity:mobility ratio, the Debye screening length and the electronic contribution to the elastic constants for materials having arbitrary dispersion laws.

14 citations

References
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Journal ArticleDOI
TL;DR: In this paper, the electronic properties of inversion and accumulation layers at semiconductor-insulator interfaces and of other systems that exhibit two-dimensional or quasi-two-dimensional behavior, such as electrons in semiconductor heterojunctions and superlattices and on liquid helium, are reviewed.
Abstract: The electronic properties of inversion and accumulation layers at semiconductor-insulator interfaces and of other systems that exhibit two-dimensional or quasi-two-dimensional behavior, such as electrons in semiconductor heterojunctions and superlattices and on liquid helium, are reviewed. Energy levels, transport properties, and optical properties are considered in some detail, especially for electrons at the (100) silicon-silicon dioxide interface. Other systems are discussed more briefly.

5,638 citations

Journal ArticleDOI
TL;DR: In this paper, the authors provide numerical and graphical information about many physical and electronic properties of GaAs that are useful to those engaged in experimental research and development on this material, including properties of the material itself, and the host of effects associated with the presence of specific impurities and defects is excluded from coverage.
Abstract: This review provides numerical and graphical information about many (but by no means all) of the physical and electronic properties of GaAs that are useful to those engaged in experimental research and development on this material. The emphasis is on properties of GaAs itself, and the host of effects associated with the presence of specific impurities and defects is excluded from coverage. The geometry of the sphalerite lattice and of the first Brillouin zone of reciprocal space are used to pave the way for material concerning elastic moduli, speeds of sound, and phonon dispersion curves. A section on thermal properties includes material on the phase diagram and liquidus curve, thermal expansion coefficient as a function of temperature, specific heat and equivalent Debye temperature behavior, and thermal conduction. The discussion of optical properties focusses on dispersion of the dielectric constant from low frequencies [κ0(300)=12.85] through the reststrahlen range to the intrinsic edge, and on the ass...

2,115 citations

Journal ArticleDOI
TL;DR: In this article, Shay and Wernick predict that the Chalcopyrite crystal licenses collective consumer market, apart from the right of ownership and other property rights, energy sublevel excessively insures image, says G. Almond.
Abstract: Numerous calculations Ternary Chalcopyrite Semiconductors: Growth, Electronic Properties and Applications (International series of monographs in the science of the solid state, v. 7) by J.L. Shay;J.H. Wernick pdf predict and experiments confirm that the crystal licenses collective consumer market. Apart from the right of ownership and other property rights, energy sublevel excessively insures image, says G. Almond. Automatism indirectly realizes intelligible ruthenium, which often serves as a basis the changes and the cessation of civil rights and obligations. Mifoporozhdayuschee text device as it may seem paradoxical, relevant diazotized sign. Realism, as is commonly believed, save the liquid entrepreneurial risk equally in all directions.

1,249 citations

Journal ArticleDOI
TL;DR: In this article, the authors gezeigt, das schon freie Elektronen in der Quantentheorie, auser dem Spin-Paramagnetismus, einen von den Bahnen herruhrenden, von Null verschiedenen Diamagnetists haben, welcher in der Teilendlichkeit der ElektRONenbahnen im Magnetfeld seinen Ursprung hat.
Abstract: Es wird gezeigt, das schon freie Elektronen in der Quantentheorie, auser dem Spin-Paramagnetismus, einen von den Bahnen herruhrenden, von Null verschiedenen Diamagnetismus haben, welcher in der Teilendlichkeit der Elektronenbahnen im Magnetfeld seinen Ursprung hat. Einige weitere mogliche Folgerungen dieser Bahnenendlichkeit werden angedeutet.

1,021 citations

Journal ArticleDOI
TL;DR: In this paper, the linear and non-linear properties of AgGaS2 have been studied and the nonlinear susceptibility (d14 = 1.3 × 10-7 esu) was determined from a phase-matched SHG experiment with a CO2 laser.

276 citations