Topological Insulators (TI) represent a hot-topic for both basic physics and promising applications because of the in-plane spin-polarized surface states (TSS) arising within the bulk insulating energy gap. The backscattering protection and the control of the spin polarization using ultrashort light pulses open new scenarios in the use of this class of materials for future opto-spintronic devices. Using time- and angle-resolved photoemission spectroscopy on SbxBi(2-x)SeyTe(3-y) class we studied the response of spin-polarized electrons to ultrashort circularly-polarized pulses. Here, we report for the first time the experimental evidence of a direct coupling between light and empty topological surface states (ESS) and the establishment of a flow of spin-polarized electrons in k-space i.e. a photon-induced spin-current.

Circularly polarized light interaction in topological insulators investigated by time-resolved ARPES

Bugini, D.;Hedayat, H.;Zhou, X.;Manzoni, C.;Dallera, C.;Cerullo, G.;Carpene, E.
2017-01-01

Abstract

Topological Insulators (TI) represent a hot-topic for both basic physics and promising applications because of the in-plane spin-polarized surface states (TSS) arising within the bulk insulating energy gap. The backscattering protection and the control of the spin polarization using ultrashort light pulses open new scenarios in the use of this class of materials for future opto-spintronic devices. Using time- and angle-resolved photoemission spectroscopy on SbxBi(2-x)SeyTe(3-y) class we studied the response of spin-polarized electrons to ultrashort circularly-polarized pulses. Here, we report for the first time the experimental evidence of a direct coupling between light and empty topological surface states (ESS) and the establishment of a flow of spin-polarized electrons in k-space i.e. a photon-induced spin-current.
2017
Physics and Astronomy (all)
File in questo prodotto:
File Dimensione Formato  
11311-1041007 Dallera.pdf

accesso aperto

: Publisher’s version
Dimensione 484.43 kB
Formato Adobe PDF
484.43 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11311/1041007
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact