An expression is derived for the diffusivity-mobility ratio of the carriers in n-channel inversion layers on semiconductors like the ternary compounds which have strongly non-parabolic energy bands. The dependence of the ratio on alloy composition is also studied under the weak-field limit taking n-channel Hg1-xCdx.Te as an example. © 1980 Academia, Publishing House of the Czechoslovak Academy of Sciences.

A N CHAKRAVARTI

A K CHOWDHURY

K P GHATAK

D R CHOUDHURY

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

Influence of alloy composition on the diffusivity-mobility ratio in n-channel inversion layers on ternary semiconductors

Czechoslovak Journal of Physics

We study theoretically the interband optical-absorption coefficient (OAC) of optoelectronic materials within the framework of the three-band model of Kane [J. Phys. Chem. Solids 12, 181 (1959)] in the presence of an external electric field for modified photon energy (ℏ ω1) below and above the band gap (Eg), respectively. The optical matrix element depends on the electron wave vector k and this practical aspect has been incorporated in the present analysis. It has been found, taking InAs, InSb, Hg1-x Cdx Te, and In1-x Gax Asy P1-y lattice matched to InP as examples of optoelectronic compounds for numerical computations, that for modified photon energies below the band gap, the OAC exhibits an exponential fall off with the electric field and the photon energy, respectively. For the opposite inequality, the OAC oscillates with the modified photon energy without the consideration of the Wannier-Stark levels, which generally exist in a band due to the presence of an external electric field. In both cases, the OAC exhibits the singularity when the incident photon energy (ℏ ω0) tends to Eg and the magnitude of the OAC depends to a large extent on the numerical values of the energy-band constants of the said compounds. In addition, the simplified results of the OAC for materials having parabolic energy bands have also been obtained from the present generalized analysis under certain limiting conditions. © 2005 American Institute of Physics.

Journal	Czechoslovak Journal of Physics
Publisher	Kluwer Academic Publishers
ISSN	0011-4626