Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effects of strain on the valence band structure and exciton-polariton
  energies in ZnO   The uniaxial stress dependence of the band structure and the
exciton-polariton transitions in wurtzite ZnO is thoroughly studied using
modern first-principles calculations based on the HSE+G0W0 approach, k p
modeling using the deformation potential framework, and polarized
photoluminescence measurements. The ordering of the valence bands [A(G7),
B(G9), C(G7)] is found to be robust even for high uniaxial and biaxial strains.
Theoretical results for the uniaxial pressure coefficients and splitting rates
of the A, B, and C valence bands and their optical transitions are obtained
including the effects of the spin-orbit interaction. The excitonic deformation
potentials are derived and the stress rates for hydrostatic pressure are
determined based on the results for uniaxial and biaxial stress. In addition,
the theory for the stress dependence of the exchange interaction and
longitudinal-transversal splitting of the exciton-polaritons is developed using
the basic exciton functions of the quasi-cubic approximation and taking the
interaction between all exciton states into account. It is shown that the
consideration of these effects is crucial for an accurate description of the
stress dependence of the optical spectra in ZnO. The theoretical results are
compared to polarized photoluminescence measurements of different ZnO
substrates as function of uniaxial pressure and experimental values reported in
the literature demonstrating an excellent agreement with the computed pressure
coefficients.

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The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat