2015/11/16 by Fang Fang, Ryan Olf, Shun Wu +3 · 2 citations
Physics and Astronomy · #Bose gas #Bose–Einstein condensate #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Degenerate energy levels #Ferromagnetism #Magnetic field #Magnetization #Magnon #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Quantum, superfluid, helium dynamics #Spin (aerodynamics) #Spin wave #Spinor #Yttrium iron garnet #cond-mat.quant-gas
paper · pdf · doi:10.1103/physrevlett.116.095301
published as Phys. Rev. Lett. 116, 095301 (2016) · 5 pages, 3 figures
arxiv created 2015/11/16 · openalex publication_date 2016/03/01 · arxiv updated 2016/03/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We observe the quasicondensation of magnon excitations within an F=1 87Rb spinor Bose-Einstein condensed gas. Magnons are pumped into a ferromagnetically ordered gas, allowed to equilibrate to a nondegenerate distribution, and then cooled evaporatively at near-constant net longitudinal magnetization, whereupon they condense. The critical magnon number, spatial distribution, and momentum distribution indicate that magnons condense in a potential that is uniform within the volume of the ferromagnetic condensate. The macroscopic transverse magnetization produced by the degenerate magnon gas remains inhomogeneous within the ∼10 s equilibration time accessed in our experiment, and includes signatures of Mermin-Ho spin textures that appear as phase singularities in the magnon quasicondensate wave function.