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arXiv · 2308.00045

Large circular photogalvanic effect in the noncentrosymmetric magnetic Weyl semimetal CeAlSi

Abhirup Roy Karmakar·A. Taraphder·G. P. Das
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Abstract

The recent discovery of the Weyl semimetal CeAlSi with simultaneous breaking of inversion and time-reversal symmetries has opened up new avenues for research into the interaction between light and topologically protected bands. In this work, we present a comprehensive examination of the shift current and injection current responsible for the circular photogalvanic effect in CeAlSi using first-principles calculations. Our investigation identifies a significant injection current of 4 mA/V$^2$ over a broad range in the near-infrared region of the electromagnetic spectrum, exceeding previously reported findings. In addition, we explored several externally controllable parameters to further enhance the photocurrent. A substantial boost in the injection current is observed when applying uniaxial strain along the $c$ axis of the crystal: a 5% strain results in a remarkable 64% increment. The exceptional photocurrent response in CeAlSi suggests that magnetic non-centrosymmetric Weyl semimetals may provide promising opportunities for novel photogalvanic applications.

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Abhirup Roy Karmakar, A. Taraphder, G. P. Das. 2023-07-31. Large circular photogalvanic effect in the noncentrosymmetric magnetic Weyl semimetal CeAlSi. https://doi.org/10.1103/physrevb.111.195105

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