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Magnetic field-Induced Nonlinear Optical Responses in Inversion Symmetric Dirac Semimetals

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 Added by Alberto Cortijo
 Publication date 2016
  fields Physics
and research's language is English




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We show that, under the effect of an external magnetic field, a photogalvanic effect and the generation of second harmonic wave can be induced in inversion-symmetric and time reversal invariant Dirac semimetals. The mechanism responsible of these non linear optical responses is the magnetochiral effect. The origin of this magnetochiral effect is the band bending of the dispersion relation in real Dirac semimetals. Some observable consequences of this phenomenon are the appearance of a dc current on the surface of the system when it is irradiated with linearly polarized light or a rotation of the polarization plane of the reflected second harmonic wave.



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