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arXiv · 2202.01522

Circular photogalvanic effects in topological insulator/ferromagnet hybrid structures

T. Schumann·T. Kleinke·L. Braun·N. Meyer·G. Mussler·J. Kampmeier·D. Grützmacher·E. Schmoranzerova·K. Olejník·H. Reichlová·C. Heiliger·C. Denker·J. Walowski·T. Kampfrath·M. Münzenberg
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Abstract

We study laser driven spin-current effects at ferromagnet/topological-insulator interfaces by two complementary experimental approaches. The DC photocurrent is studied in ferromagnet/topological-insulator bilayers with high spatial resolution. Dynamic interface currents are explored via the emission of terahertz radiation emitted by these currents with high temporal resolution. From our experiments, we reveal a lateral and dynamic interaction of the ferromagnet and the topological insulator interface.

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T. Schumann, T. Kleinke, L. Braun, N. Meyer, G. Mussler, J. Kampmeier, D. Grützmacher, E. Schmoranzerova, K. Olejník, H. Reichlová, C. Heiliger, C. Denker, J. Walowski, T. Kampfrath, M. Münzenberg. 2022-02-03. Circular photogalvanic effects in topological insulator/ferromagnet hybrid structures. https://arxiv.org/abs/2202.01522

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