Twisted Schwinger effect - geometric effects in pair production by rotating fields -

by Prof. Shintaro Takayoshi (Konan University)

Monday 18 May 2020, 13:30 → 14:30 Asia/Shanghai

ONLINE

Abstract

We study the fermion-antifermion pair production in Dirac systems induced by strong rotating electric fields, which we refer as the "twisted Schwinger effect". Due to the circularly polarization, the geometric effects appear in the quantum tunneling process of pair production. Nonadiabatic geometric effects predict phenomena such as gapped perfect tunneling and counterdiabatic driving, which respectively leads to a decrease and increase of the Schwinger limit, the tunneling threshold. As a condensed matter realization, we predict an optically induced valley polarization in 2D Dirac materials, and the generation of a nonlinear chiral or spin current in 3D Dirac materials.

Biography

2012 PhD at the University of Tokyo, Japan (supervisor: Masaki Oshikawa)

2012-2013 Postdoc at the University of Tokyo, Japan (worked with Takashi Oka)

2013-2015 Postdoc at National Institute of Materials Science, Tsukuba, Japan

2015-2018 Postdoc at the University of Geneva, Switzerland (worked with Thierry Giamarchi)

2018-2020 Postdoc at Max Planck Institute for the Physics of Complex Systems, Dresden, Germany (worked with Takashi Oka)

2020- Associate Professor at Konan University, Kobe, Japan 

Research topic: Dynamics induced by laser fields in electron and spin systems

Division

Condensed Matter

Other information

Venue: TDLI Meeting Room 200

Here is the Zoom link if you prefer to join us remotely:

Meeting room: https://us02web.zoom.us/j/83883476228