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Longitudinal Spin Diffusion in a Nondegenerate Trapped ^{87}Rb Gas
D Niroomand1, S D Graham1, J M McGuirk1
1Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
Physical Review Letters
|August 29, 2015
Summary
Coherent domain walls in ultracold rubidium-87 gas slow spin diffusion and alter oscillation frequencies. This quantum coherence leads to spin conversion and increased system coherence.
Area of Science:
- Atomic physics
- Quantum dynamics
- Condensed matter physics
Background:
- Investigating spin dynamics in ultracold atomic gases is crucial for understanding quantum phenomena.
- Trapped atomic systems provide a controllable platform for studying fundamental quantum interactions.
Purpose of the Study:
- To study longitudinal spin diffusion in a trapped Rubidium-87 sample.
- To investigate the impact of domain wall coherence on spin dynamics.
Main Methods:
- Utilizing a trapped Rubidium-87 sample above quantum degeneracy.
- Analyzing the longitudinal spin diffusion and domain wall dynamics.
Main Results:
- Coherence in the domain wall results in slower-than-classical transverse-spin-mediated longitudinal spin diffusion.
- Domain wall coherence alters the oscillation frequency of pseudospin domains.
- Observed instability in longitudinal spin dynamics due to spin component coupling.
- Demonstrated conversion of longitudinal spin to transverse spin, increasing overall system coherence.
Conclusions:
- Domain wall coherence significantly modifies spin diffusion and dynamics in ultracold atomic systems.
- The coupling between longitudinal and transverse spins can lead to spin conversion and enhanced coherence.
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