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arXiv · 1810.11403

Matrix-element induced spin polarization of photoelectrons from bulk bands

Dmitry Vasilyev·Katerina Medjanik·Sergey Babenkov·Martin Ellguth·Gerd Schönhense·Hans-Joachim Elmers
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Abstract

Angular- or $k$-resolved photoelectron spectroscopy in the soft X-ray range gives access to the bulk electronic structure of materials. Here this technique is extended to the spin degree of freedom. A non-magnetic material (tungsten) was chosen, in order to exclude any initial-state spin polarization from exchange-split bands. By measurement of two spin-polarizations for different light helicity, one can distinguish between contributions of optical spin-orientation by circularly-polarized X-rays (Fano componen) and a second component originating from interference of final-state partial waves. Both phenomena have so far only been observed at low photon energies. Their detection in the X-ray range is a milestone on the way to the "complete experiment" in bulk photoemission.

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Dmitry Vasilyev, Katerina Medjanik, Sergey Babenkov, Martin Ellguth, Gerd Schönhense, Hans-Joachim Elmers. 2018-10-26. Matrix-element induced spin polarization of photoelectrons from bulk bands. https://arxiv.org/abs/1810.11403

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