Efecto de la concentración de Ga sobre las propiedades electrónicas del CuIn1−XGaXSe2 (Ga Concentration Effect on the CuIn1-xGaxSe2 Electronic Properties)

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Autores

D. A. Rasero Causil
A. A. Portacio Lamadrid
J. A. Rodríguez

Resumen

Resumen

Se reportan cálculos de propiedades electrónicas del compuesto CuIn1−xGaxSe2 (x = 0,0, 0,2, 0,4, 0,6, 0,8, 1,0), usando el método Tight-Binding (TB) y Virtual Crystal Approximation (VCA). Se considera el caso ideal y con las distorsiones tetragonal (η) y aniónica (μ). En ambos casos, el CuIn1−xGaxSe2 es un semiconductor directo en Γ, para todas las concentraciones. Se encontró que el Crystal Field Splitting (CFS) en el punto Γ depende principalmente de la distorsión tetragonal. El CFS es positivo para x &lt, 0,32 y negativo para x &gt, 0,32. Este comportamiento se debe a que cuando aumenta x, la celda unitaria se contrae, acercando el pseudoátomo (In,Ga) al átomo de Se.

 

Abstract

 

This paper reports some calculations of the electronic properties of CuIn1-xGaxSe2 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) compound, by using the Tight-Binding (TB) method and Virtual Crystal Approximation (VCA). It is considered the ideal case and with the tetragonal () and anionic () distortions. In both cases, the CuIn1-xGaxSe2 is a direct semiconductor at Γ, for all concentrations.It was found that the Crystal Field Splitting (CFS) at the Γ point depends mainly on the tetragonal distortion. The CFS is positive for x &lt, 0,32 and negative for x &gt, 0.32. This behavior is due that when x is increasing, the unit cell shrinks, approaching the pseudo-atom (In,Ga) to the Se atom.

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Referencias

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