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arXiv · 1512.04055

Determine the chirality of Weyl fermions from the circular dichroism spectra of time-dependent ARPES

Rui Yu·Hongming Weng·Zhong Fang·Hong Ding·Xi Dai
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Abstract

We show that the intensity of pumped states near Weyl point is different when pumped with left- and right-handed circular polarized light, which leads to a special circular dichroism (CD) in time-dependent angle resolved photoemission spectra (ARPES). We derive the expression for the CD of time-dependent ARPES, which is directly related to the chirality of Weyl fermions. Based on the above derivation, we further propose a method to determine the chirality for a given Weyl point from the CD of time-dependent ARPES. The corresponding CD spectra for TaAs has then been calculated from the first principle, which can be compared with the future experiments.

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Rui Yu, Hongming Weng, Zhong Fang, Hong Ding, Xi Dai. 2015-12-13. Determine the chirality of Weyl fermions from the circular dichroism spectra of time-dependent ARPES. https://doi.org/10.1103/physrevb.93.205133

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