Coherent ultrafast spin-dynamics probed in three dimensional topological insulators

F. Boschini; M. Mansurova; G. Mussler; J. Kampmeier; D. Grützmacher; L. Braun; F. Katmis; J. S. Moodera; C. Dallera; E. Carpene; C. Franz; M. Czerner; C. Heiliger; T. Kampfrath; M. Münzenberg

doi:10.1038/srep15304

arXiv · 1506.02692

Coherent ultrafast spin-dynamics probed in three dimensional topological insulators

F. Boschini·M. Mansurova·G. Mussler·J. Kampmeier·D. Grützmacher·L. Braun·F. Katmis·J. S. Moodera·C. Dallera·E. Carpene·C. Franz·M. Czerner·C. Heiliger·T. Kampfrath·M. Münzenberg

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Abstract

Topological insulators are candidates to open up a novel route in spin based electronics. Different to traditional ferromagnetic materials, where the carrier spin-polarization and magnetization are based on the exchange interaction, the spin properties in topological insulators are based on the coupling of spin- and orbit interaction connected to its momentum. Specific ways to control the spin-polarization with light have been demonstrated: the energy momentum landscape of the Dirac cone provides spin-momentum locking of the charge current and its spin. The directionality of spin and momentum, as well as control with light has been demonstrated. Here we demonstrate a coherent femtosecond control of spin-polarization for states in the valence band at around the Dirac cone.

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F. Boschini, M. Mansurova, G. Mussler, J. Kampmeier, D. Grützmacher, L. Braun, F. Katmis, J. S. Moodera, C. Dallera, E. Carpene, C. Franz, M. Czerner, C. Heiliger, T. Kampfrath, M. Münzenberg. 2015-06-08. Coherent ultrafast spin-dynamics probed in three dimensional topological insulators. https://doi.org/10.1038/srep15304

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