2007/03/31 by Tudor D. Stanescu, Chuanwei Zhang, Victor Galitski · 16 citations
Physics and Astronomy · #Advanced Frequency and Time Standards #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Coupling (piping) #Electron #Fermi gas #Fermion #Non-equilibrium thermodynamics #Physics #Polarization (electrochemistry) #Quantum mechanics #Relaxation (psychology) #Spin (aerodynamics) #Spin polarization #cond-mat.other
paper · pdf · doi:10.1103/physrevlett.99.110403
published as Phys. Rev. Lett. 99, 110403 (2007) · 5 pages, 4 figures; published version
openalex publication_date 2007/09/14 · arxiv created 2007/12/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider a trapped atomic system in the presence of spatially varying laser fields. The laser-atom interaction generates a pseudospin degree of freedom (referred to simply as spin) and leads to an effective spin-orbit coupling for the fermions in the trap. Reflections of the fermions from the trap boundaries provide a physical mechanism for effective momentum relaxation and nontrivial spin dynamics due to the emergent spin-orbit coupling. We explicitly consider evolution of an initially spin-polarized Fermi gas in a two-dimensional harmonic trap and derive nonequilibrium behavior of the spin polarization. It shows periodic echoes with a frequency equal to the harmonic trapping frequency. Perturbations, such as an asymmetry of the trap, lead to the suppression of the spin echo amplitudes. We discuss a possible experimental setup to observe spin dynamics and provide numerical estimates of relevant parameters.