Control of the Bose-Einstein Condensation of Magnons by the Spin-Hall Effect

Michael Schneider; David Breitbach; Rostyslav O. Serha; Qi Wang; Alexander A. Serga; Andrei N. Slavin; Vasyl S. Tiberkevich; Björn Heinz; Bert Lägel; Thomas Brächer; Carsten Dubs; Sebastian Knauer; Oleksandr V. Dobrovolskiy; Philipp Pirro; Burkard Hillebrands; Andrii V. Chumak

doi:10.1103/physrevlett.127.237203

arXiv · 2102.13481

Control of the Bose-Einstein Condensation of Magnons by the Spin-Hall Effect

Michael Schneider·David Breitbach·Rostyslav O. Serha·Qi Wang·Alexander A. Serga·Andrei N. Slavin·Vasyl S. Tiberkevich·Björn Heinz·Bert Lägel·Thomas Brächer·Carsten Dubs·Sebastian Knauer·Oleksandr V. Dobrovolskiy·Philipp Pirro·Burkard Hillebrands·Andrii V. Chumak

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Abstract

Previously, it has been shown that rapid cooling of yttrium-iron-garnet (YIG)/platinum (Pt) nano structures, preheated by an electric current sent through the Pt layer, leads to overpopulation of a magnon gas and to subsequent formation of a Bose-Einstein condensate (BEC) of magnons. The spin Hall effect (SHE), which creates a spin-polarized current in the Pt layer, can inject or annihilate magnons depending on the electric current and applied field orientations. Here we demonstrate that the injection or annihilation of magnons via the SHE can prevent or promote the formation of a rapid cooling induced magnon BEC. Depending on the current polarity, a change in the BEC threshold of -8% and +6% was detected. These findings demonstrate a new method to control macroscopic quantum states, paving the way for their application in spintronic devices.

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physics.app-ph cond-mat.mes-hall cond-mat.quant-gas

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Michael Schneider, David Breitbach, Rostyslav O. Serha, Qi Wang, Alexander A. Serga, Andrei N. Slavin, Vasyl S. Tiberkevich, Björn Heinz, Bert Lägel, Thomas Brächer, Carsten Dubs, Sebastian Knauer, Oleksandr V. Dobrovolskiy, Philipp Pirro, Burkard Hillebrands, Andrii V. Chumak. 2021-02-26. Control of the Bose-Einstein Condensation of Magnons by the Spin-Hall Effect. https://doi.org/10.1103/physrevlett.127.237203

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