Valley polarization control in WSe2 monolayer by a single-cycle laser pulse

  title={Valley polarization control in WSe2 monolayer by a single-cycle laser pulse},
  author={Arqum Hashmi and Shunsuke Yamada and Atsushi Yamada and Kazuhiro Yabana and Tomohito Otobe},
The valley degree of freedom in two-dimensional materials provides an opportunity to extend the functionalities of valleytronics devices. Very short valley lifetimes demand the ultrafast control of valley pseudospin. Here, we theoretically demonstrate the control of valley pseudospin in WSe2 monolayer by single-cycle linearly polarized laser pulse. We use the asymmetric electric field controlled by the carrier-envelope phase (CEP) to make the valley polarization between K and K ′ -point in the… 
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