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arXiv · 2209.12360

Optical protection of alkali-metal atoms from spin relaxation

Avraham Berrebi·Mark Dikopoltsev·Ori Katz·Or Katz
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Abstract

We present an optical technique for suppressing relaxation in alkali-metal spins using a single off-resonant laser beam. The method harnesses a physical mechanism that synchronizes Larmor precession in the two hyperfine manifolds, protecting magnetic coherence from relaxation caused by spin-exchange and other hyperfine-changing collisions. We experimentally demonstrate up to a ninefold reduction in decoherence of warm cesium vapor, achieving simultaneous protection from both spin-exchange relaxation and partial depolarization from coated cell walls. The technique substantially enhances the spin precession quality factor and maintains a stable gyromagnetic ratio independent of spin polarization, even under frequent collisions. These findings offer a pathway for mitigating dominant relaxation channels in alkali-metal-based applications and experiments, particularly in anti-relaxation-coated cells.

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Avraham Berrebi, Mark Dikopoltsev, Ori Katz, Or Katz. 2022-09-26. Optical protection of alkali-metal atoms from spin relaxation. https://doi.org/10.1103/fncz-b3yy

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