Bose-Einstein Condensation of Magnons and Spin Superfluidity in the Polar Phase of HE 3

S. Autti, V. V. Dmitriev, J. T. Mäkinen, J. Rysti, A. A. Soldatov, G. E. Volovik, A. N. Yudin, V. B. Eltsov

Research output: Contribution to journalArticleScientificpeer-review

5 Citations (Scopus)
183 Downloads (Pure)

Abstract

The polar phase of He3, which is topological spin-triplet superfluid with the Dirac nodal line in the spectrum of Bogoliubov quasiparticles, has been recently stabilized in a nanoconfined geometry. We pump magnetic excitations (magnons) into the sample of polar phase and observe how they form a Bose-Einstein condensate, revealed by coherent precession of the magnetization of the sample. Spin superfluidity, which supports this coherence, is associated with the spontaneous breaking of U(1) symmetry by the phase of precession. We observe the corresponding Nambu-Goldstone boson and measure its mass emerging when applied rf field violates the U(1) symmetry explicitly. We suggest that the magnon BEC in the polar phase is a powerful probe for topological objects such as vortices and solitons and topological nodes in the fermionic spectrum.

Original languageEnglish
Article number025303
Pages (from-to)1-6
JournalPhysical Review Letters
Volume121
Issue number2
DOIs
Publication statusPublished - 12 Jul 2018
MoE publication typeA1 Journal article-refereed

Fingerprint Dive into the research topics of 'Bose-Einstein Condensation of Magnons and Spin Superfluidity in the Polar Phase of HE 3'. Together they form a unique fingerprint.

  • Equipment

    OtaNano

    Anna Rissanen (Manager)

    Aalto University

    Facility/equipment: Facility

  • Cite this