Demagnetization dynamics of non-interacting trapped fermions

Abstract

Motivated by several experimental efforts to understand spin diffusion and transport in ultracold fermionic gases, we study the spin dynamics of initially spin-polarized ensembles of harmonically trapped non-interacting spin-1/2 fermionic atoms, subjected to a magnetic field gradient. We obtain simple analytic expressions for spin observables in the presence of both constant and linear magnetic field gradients, with and without a spin-echo pulse, and at zero and finite temperatures. The analysis shows the relevance of spin-motional coupling in the non-interacting regime where the demagnetization decay rate at short times can be faster than the experimentally measured rates in the strongly interacting regime under similar trapping conditions. Our calculations also show that particle motion limits the ability of a spin-echo pulse to remove the effect of magnetic field inhomogeneity, and that a spin-echo pulse can instead lead to an increased decay of magnetization at times comparable to the trapping period.

References in corpus (9)

• Non-equilibrium spin dynamics in a trapped Fermi gas with effective spin-orbit interaction
• Transverse Demagnetization Dynamics of a Unitary Fermi Gas
• Observation of Anomalous Spin Segregation in a Trapped Fermi Gas
• Universal spin dynamics in two-dimensional Fermi gases
• Observation of the Leggett-Rice effect in a unitary Fermi gas
• Spin diffusion in Fermi gases
• Spin dynamics in a spin-orbit coupled Fermi gas
• Spin Drag of a Fermi Gas in a Harmonic Trap
• Collisionless spin dynamics in a magnetic field gradient

Cited by in corpus (11)

• A unified ab-initio approach to the correlated quantum dynamics of ultracold fermionic and bosonic mixtures
• Observation of a Transition Between Dynamical Phases in a Quantum Degenerate Fermi Gas
• Extending rotational coherence of interacting polar molecules in a spin-decoupled magic trap
• Sub-millisecond Entanglement and iSWAP Gate between Molecular Qubits
• Universal Spin Transport and Quantum Bounds for Unitary Fermions
• Dynamics of interacting fermions in spin-dependent potentials
• Probing Ferromagnetic Order in Few-Fermion Correlated Spin-Flip Dynamics
• Exact calculation of phonon effects on spin squeezing
• Analog Simulation of Weyl Particles with Cold Atoms
• Spin-charge correlations in finite one-dimensional multi-band Fermi systems
• Crossover from collisionless to collisional spin dynamics of polarized fermions