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arXiv · 2309.11123

Optically driven spin-alignment precession

A. A. Fomin·M. Yu. Petrov·A. S. Pazgalev·G. G. Kozlov·V. S. Zapasskii
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Abstract

The effect of optically driven spin precession discovered by Bell and Bloom [W. E. Bell and A. L. Bloom, Phys. Rev. Lett. 6, 280 (1961)] is widely used nowadays as a basis for numerous experiments in fundamental physics and for diverse applications. In this paper we consider a much less popular version of the light-induced spin precession that does not imply coherent precession of the spin-system magnetization and is excited by linearly (rather than circularly) polarized light. Pump-probe measurements performed on the D2 line of cesium vapor show that the magnitude of the signal of the optically driven spin-alignment precession, in "vacuum" cells (with no buffer gas) is close to that of classical spin-orientation precession. In the presence of buffer gas, however, the signal of spin-alignment precession appears to be strongly suppressed. The discovered effect is ascribed to spin mixing of excited states of cesium atoms in the cycle of optical pumping.

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A. A. Fomin, M. Yu. Petrov, A. S. Pazgalev, G. G. Kozlov, V. S. Zapasskii. 2023-10-20. Optically driven spin-alignment precession. https://doi.org/10.1103/physreva.108.043109

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