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Energy bands and Wannier-Mott excitons in Zn(P_{1-x}As_{x})_{2} and Zn_{1-x}Cd_{x}P_{2} crystals

O. A. Yeshchenko·M. M. Biliy·Z. Z. Yanchuk
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Abstract

Excitonic absorption, reflection and photoluminescence spectra of mixed Zn(P_{1-x}As_{x})_{2}crystals over the full range of x (0 < x < 1) and Zn_{1-x}Cd_{x}P_{2} crystals at 0 < x < 0.05 have been studied at low temperatures (1.8 K). The decrease of the energy gap in Zn(P_{1-x}As_{x})_{2} at the increase of x occurs slightly sublinearly. The rydbergs of excitonic series in this crystals decrease as well, and the dependences Ry(x) for all series are strongly superlinear at small x. In Zn_{1-x}Cd_{x}P_{2} crystals the energy gap and rydbergs decrease at the increase of x (at 0 < x < 0.05) as well. The dependences of E_{g} and Ry on x are considerably stronger in Zn(P_{1-x}As_{x})_{2} than in Zn_{1-x}Cd_{x}P_{2}. At the increase of x the half-width of excitonic absorption lines increases monotonically in both type crystals that is evidence of the increasing role of fluctuations of crystal potential.

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O. A. Yeshchenko, M. M. Biliy, Z. Z. Yanchuk. 2002-05-07. Energy bands and Wannier-Mott excitons in Zn(P_{1-x}As_{x})_{2} and Zn_{1-x}Cd_{x}P_{2} crystals. https://arxiv.org/abs/cond-mat/0205134

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