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arXiv · 1512.01363

Spin Mapping of Surface and Bulk Rashba States in Ferroelectric a-GeTe(111) Films

H. J. Elmers·R. Wallauer·M. Liebmann·J. Kellner·M. Morgenstern·R. N. Wang·J. E. Boschker·R. Calarco·O. Rader·D. Kutnyakhov·S. V. Chernov·K. Medjanik·C. Tusche·M. Ellguth·H. Volfova·J. Braun·J. Minar·H. Ebert·G. Schonhense
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Abstract

A comprehensive mapping of the spin polarization of the electronic bands in ferroelectric a-GeTe(111) films has been performed using a time-of-flight momentum microscope equipped with an imaging spin filter that enables a simultaneous measurement of more than 10.000 data points (voxels). A Rashba type splitting of both surface and bulk bands with opposite spin helicity of the inner and outer Rashba bands is found revealing a complex spin texture at the Fermi energy. The switchable inner electric field of GeTe implies new functionalities for spintronic devices.

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H. J. Elmers, R. Wallauer, M. Liebmann, J. Kellner, M. Morgenstern, R. N. Wang, J. E. Boschker, R. Calarco, O. Rader, D. Kutnyakhov, S. V. Chernov, K. Medjanik, C. Tusche, M. Ellguth, H. Volfova, J. Braun, J. Minar, H. Ebert, G. Schonhense. 2015-12-04. Spin Mapping of Surface and Bulk Rashba States in Ferroelectric a-GeTe(111) Films. https://doi.org/10.1103/physrevb.94.201403

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