An attempt is made to investigate the effects of size quantization on the Einstein relation for the diffusivity‐mobility ratio in ultrathin films of n‐Cd3As2. It is found that the ratio increases, at a given electron concentration, with decreasing film thickness and also increases with increasing electron concentration corresponding to a given film thickness. For extremely thin films, the influence of size quantization becomes increasingly prominent with decreasing values of the electron concentration. Copyright © 1981 WILEY‐VCH Verlag GmbH &amp; Co. KGaA

A N CHAKRAVARTI

K P GHATAK

K K GHOSH

S GHOSH

H M MUKHERJEE

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

&nbsp;

The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

&nbsp;

It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

physica status solidi (b)

We study theoretically the energy spectrum of the conduction electrons and the Einstein relation for the diffusivity-mobility ratio (DMR) for III-V, ternary and quaternary materials, whose unperturbed energy band structures are defined by the three-band model of Kane, in the presence of light waves. 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 under different external conditions. It has been observed that the unperturbed isotropic energy spectrum in the presence of light changes into an anisotropic dispersion relation with the energy-dependent mass anisotropy. It has been found taking n-InAs, n-InSb, n-Hg1-xCdxTe and n-In1-xGaxAsyP1- y lattice matched to InP, as examples that the DMR increases with increasing electron concentration, decreasing with increasing intensity and wavelength in various manners. The rate of change is totally band structure dependent and is influenced by the presence of the different energy band constants. The well-known result for the DMR for degenerate 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 suggested an experimental method of determining the DMR in degenerate materials having arbitrary dispersion laws. © 2007 Elsevier B.V. All rights reserved.

Physica B: Condensed Matter

Influence of light on the Einstein relation in III-V, ternary and quaternary materials: Simplified theory and a suggestion for experimental determination

The Einstein relation for the diffusivity-mobility ratio of the carriers in semiconductors (hereeafter referred to as DMR) is a very important one, since by being a thermo-dynamic relation this is independent of any scattering mechanisms and also since one can determine the diffusivity from this relation by knowing the mobility and vice-versa. besides, the simplest method of analyzing semiconductor devices taking into account the degeneracy of the bands is to use the DMR to express the performance at the device terminals and the switching speed in terms of carrier concentration. © 1987 SPIE.

Proceedings of SPIE - The International Society for Optical Engineering

On the einstein relation in superlattices of kane - type semiconductors in the presence of a quantizing magnetic field

An attempt is made to study the effect of crystal‐field splitting on the Einstein relation for the diffusivity‐mobility ratio of the carriers in tetragonal semiconductors, taking inherently degenerate n‐Cd3As2 as an example. It is found on the basis of the Bodnar model, which has recently been demonstrated in the literature to be the most valid model for Cd3As2, that the above ratio increases with increasing carrier concentration as expected for degenerate semiconductors. It is also shown that the tetragonal crystal‐field effectively reduces the ratio with increasing amount of reduction with increasing carrier concentration. Copyright © 1983 WILEY‐VCH Verlag GmbH &amp; Co. KGaA

Journal	physica status solidi (b)
Publisher	-
ISSN	0370-1972