Generation of atomic spin orientation with a linearly polarised beam in room-temperature alkali-metal vapour

TL;DR

This paper demonstrates a novel method for generating atomic spin orientation in room-temperature caesium vapours by combining optical pumping, non-linear spin dynamics, and spin-exchange collisions, enabling simpler atomic magnetometers.

Contribution

It introduces a new mechanism for atomic spin orientation that simplifies the setup for RF atomic magnetometers using a single low-power laser.

Findings

Transition between aligned and oriented atomic states observed.

Spin-exchange relaxation rate controls the orientation state.

Potential for robust, low-power atomic magnetometers.

Abstract

Traditionally, atomic spin orientation is achieved by the transfer of angular momentum from polarised light to an atomic system. We demonstrate the mechanism of orientation generation in room-temperature caesium vapours that combines three elements: optical pumping, non-linear spin dynamics and spin-exchange collisions. Through the variation of the spin-exchange relaxation rate, the transition between an aligned and an oriented atomic sample is presented. The observation is performed by monitoring the atomic radio-frequency spectra. The measurement configuration discussed, paves the way to simple and robust radio-frequency atomic magnetometers that are based on a single low power laser diode that approach the performance of multi-laser pump-probe systems.