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arXiv · 1906.07627

Directional shift current in mirror-symmetric BC$_2$N

J. Ibañez-Azpiroz·I. Souza·F. de Juan
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Abstract

We present a theoretical study of the shift current in a noncentrosymmetric polytype of graphitic BC$_2$N. We find that the photoconductivity near the fundamental gap is strongly anisotropic due to the vanishing of particular tensor components not foretold by point-group symmetry arguments; this is a consequence of dipole selection rules imposed by mirror symmetry, which imply that the relative parities between valence and conduction bands are key for determining the directionality of the band-edge response. In addition, the band-edge photoconductivity turns out to be rather large, with the peak value occurring in an energy range suitable for optical manipulation

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J. Ibañez-Azpiroz, I. Souza, F. de Juan. 2019-06-18. Directional shift current in mirror-symmetric BC$_2$N. https://doi.org/10.1103/physrevresearch.2.013263

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