Interaction-tuned dynamical transitions in a Rashba spin-orbit-coupled Fermi gas

Area of Science:

• Condensed Matter Physics
• Quantum Gases
• Spin Dynamics

Background:

• Understanding magnetization dynamics is crucial for quantum gas applications.
• Rashba spin-orbit coupling significantly influences quantum gas behavior.
• Fermi gases offer a platform for studying many-body quantum phenomena.

Purpose of the Study:

• To investigate the time evolution of magnetization in a Rashba spin-orbit coupled Fermi gas.
• To identify different dynamical regimes based on interaction and spin-orbit coupling strength.
• To explore the analogy between these dynamics and self-trapping phenomena in Bose-Einstein condensates.

Main Methods:

• Modeling the dynamics using a Boltzmann equation.
• Solving the nonlinear system within the Hartree-Fock approximation.
• Analyzing the asymptotic behavior of magnetization at long times.

Main Results:

• Identified three distinct dynamical regimes controlled by the ratio of interaction to spin-orbit coupling strength (λ).
• For small λ, magnetization decays to zero.
• For intermediate λ, magnetization exhibits undamped oscillations around zero.
• For large λ, a stable, partially magnetized state is dynamically achieved.

Conclusions:

• The interplay between interactions and spin-orbit coupling dictates the long-term magnetization behavior in Fermi gases.
• These findings reveal a spin analog of interaction-induced self-trapping.
• The predicted phenomena are experimentally achievable in trapped Fermi gases with synthetic spin-orbit interactions.