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arXiv · 2411.04733

Internal state cooling of an atom with thermal light

Amanda Younes·Randall Putnam·Paul Hamilton·Wesley C. Campbell
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Abstract

A near-minimal instance of optical cooling is experimentally presented wherein the internal-state entropy of a single atom is reduced more than twofold by illuminating it with broadband, incoherent light. Since the rate of optical pumping by a thermal state increases monotonically with its temperature, the cooling power in this scenario increases with higher thermal occupation, an example of a phenomenon known as cooling by heating. In contrast to optical pumping by coherent, narrow-band laser light, here we perform the same task with fiber-coupled, broadband sunlight, the brightest laboratory-accessible source of continuous blackbody radiation.

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Amanda Younes, Randall Putnam, Paul Hamilton, Wesley C. Campbell. 2024-11-07. Internal state cooling of an atom with thermal light. https://arxiv.org/abs/2411.04733

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