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Ab Initio calculation of band gap renormalization in highly excited GaAs

Catalin D. Spataru·Lorin X. Benedict·Steven G. Louie
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Abstract

We present ab initio quasiparticle self-energy calculations in crystalline GaAs for cases of intense electronic excitation (~ 10% of valence electrons excited into conduction band), relevant for high-intensity ultra-short pulsed laser experiments. Calculations are performed using an out-of-equilibrium generalization of the GW approximation based on the Keldysh Green's function approach. Our results indicate that while the band gap is a sensitive function of the amount of excitation, it is not possible to induce complete band gap closure in this system by purely electronic means.

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Catalin D. Spataru, Lorin X. Benedict, Steven G. Louie. 2004-08-12. Ab Initio calculation of band gap renormalization in highly excited GaAs. https://doi.org/10.1103/physrevb.69.205204

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