Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ab Initio calculation of band gap renormalization in highly excited GaAs   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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The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
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The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
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The categories of this paper are: econ
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The categories of this paper are: bayes-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom