Speaker
Davide Bugini
(ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE)
Description
We present time- and angle-resolved photoemission spectroscopy (TR-ARPES) measurements on BixSb(2−x)TeySe(3−y) topological insulators. Exploiting circularly polarized femtosecond pulses we investigated spin-related ultrafast phenomena as photo-induced spin current and spin-dependent relaxation processes.
In particular, we report the first experimental evidence of a direct coupling between light and empty topological surface states (ESS) that triggers a flow of spin-polarized electrons in k-space i.e. a photon-induced spin-current. In addition, our data suggest an accumulation of spin-polarized electrons in the conduction bands leading to a finite polarization in the surface resonance state (SRS).
Authors
Davide Bugini
(ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE)
Dr
Fabio Boschini
(Department of Physics & Astronomy, University of British Columbia)
Dr
Hamoon Hedayat
(Dipartimento di Fisica, Politecnico di Milano)
Dr
Hemian Yi
(National Lab for Superconductivity, Institute of Physics, Chinese Academy of Science)
Dr
Chaoyu Chen
(National Lab for Superconductivity, Institute of Physics, Chinese Academy of Science)
Prof.
Xingjiang Zhou
(National Lab for Superconductivity, Institute of Physics, Chinese Academy of Science)
Dr
Cristian Manzoni
(CNR-IFN, Dipartimento di Fisica, Politecnico di Milano)
Prof.
Claudia Dallera
(Dipartimento di Fisica, Politecnico di Milano)
Prof.
Giulio Cerullo
(Dipartimento di Fisica, Politecnico di Milano)
Dr
Ettore Carpene
(CNR-IFN, Dipartimento di Fisica, Politecnico di Milano)
