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Zero-bias photocurrent in ferromagnetic topological insulator.

ABSTRACT: Magnetic interactions in topological insulators cause essential modifications in the originally mass-less surface states. They offer a mass gap at the Dirac point and/or largely deform the energy dispersion, providing a new path towards exotic physics and applications to realize dissipation-less electronics. The nonequilibrium electron dynamics at these modified Dirac states unveil additional functions, such as highly efficient photon to spin-current conversion. Here we demonstrate the generation of large zero-bias photocurrent in magnetic topological insulator thin films on mid-infrared photoexcitation, pointing to the controllable band asymmetry in the momentum space. The photocurrent spectra with a maximal response to the intra-Dirac-band excitations can be a sensitive measure for the correlation between Dirac electrons and magnetic moments.

SUBMITTER: Ogawa N

PROVIDER: S-EPMC4961789 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Zero-bias photocurrent in ferromagnetic topological insulator.

Ogawa N N Yoshimi R R Yasuda K K Tsukazaki A A Kawasaki M M Tokura Y Y

Nature communications 20160720

Magnetic interactions in topological insulators cause essential modifications in the originally mass-less surface states. They offer a mass gap at the Dirac point and/or largely deform the energy dispersion, providing a new path towards exotic physics and applications to realize dissipation-less electronics. The nonequilibrium electron dynamics at these modified Dirac states unveil additional functions, such as highly efficient photon to spin-current conversion. Here we demonstrate the generatio ...[more]

PMID: 27435028

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