Spin current generation and relaxation in a quenched spin-orbit-coupled Bose-Einstein condensate

Area of Science:

• Condensed matter physics
• Quantum optics
• Atomic physics

Background:

• Spin-orbit coupling (SOC) and many-body interactions are crucial for spin transport in electrons.
• Spin transport in charge-neutral bosonic quasiparticles, like Bose-Einstein condensates (BECs), remains underexplored.
• BECs offer potential for coherent spin transport over macroscopic distances.

Purpose of the Study:

• To investigate the influence of synthetic SOC and atomic interactions on spin transport in atomic BECs.
• To understand the dynamics of the spin-dipole mode (SDM) in a two-component BEC under SOC.
• To explore the potential of BECs for novel spin transport phenomena.

Main Methods:

• Experimental realization of synthetic SOC in a two-component atomic BEC using optical Raman coupling.
• Actuation of the spin-dipole mode (SDM) by quenching Raman coupling.
• Theoretical modeling to analyze the effects of SOC on spin transport dynamics.

Main Results:

• Synthetic SOC significantly enhances the damping of the spin-dipole mode (SDM).
• SOC reduces thermalization, preserving the condensate fraction.
• Observation of collective excitations, such as shape oscillations, in the BEC.
• Theoretical insights into SOC-modified interference, immiscibility, and interactions influencing spin transport.

Conclusions:

• Synthetic SOC plays a critical role in modulating spin transport in atomic BECs.
• The findings open new avenues for exploring coherent spin transport in neutral quantum systems.
• This research contributes to understanding fundamental spin dynamics in condensed matter and spintronics.