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تسجيل مستخدم جديدZero temperature geometric spin dephasing on a ring in presence of an Ohmic environment
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We study zero temperature spin dynamics of a particle confined to a ring in presence of spin orbit coupling and Ohmic electromagnetic fluctuations. We show that the dynamics of the angular position $theta(t)$ are decoupled from the spin dynamics and that the latter is mapped to certain correlations of a spinless particle. We find that the spin correlations in the $z$ direction (perpendicular to the ring) are finite at long times, i.e. do not dephase. The parallel (in plane) components for spin $half$ do not dephase at weak dissipation but they probably decay as a power law with time at strong dissipation.
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