First principles calculations of the electronic and dielectric properties of λ-Ta2O5
Ta2O5 is a wide-bandgap semiconductor that offers interesting applications in microwave
communications, mainly related to the manufacture of filters and resonators whose
size is inversely proportional to the dielectric constant of the material. For that reason, in
this work we present a theoretical study, based on density functional theory (using PBEsol
and hybrid HSE06 exchange-correlation functionals), of the electronic and dielectric
properties of the orthorhombic model -Ta2O5. We found that this model has a direct gap of
2.09 and 3.7 eV with PBEsol and HSE06, respectively. Furthermore, the calculated static
dielectric constant, 51, is in good agreement with the reported values of other phases of this
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