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arXiv · 2510.13360

Efficient lambda-enhanced gray molasses using an EIT-based laser locking scheme

Timothy Leese·Siobhan Patrick·Silvia Bergamini·Calum MacCormick
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Abstract

We present a novel implementation of lambda-enhanced gray molasses cooling in a non-standard beam geometry and with an inexpensive laser locking set-up. In contrast to the established use of resource-intensive phase locking methods, our laser system uses two independent lasers, frequency -locked to a spectral feature produced by an electromagnetically induced transparency (EIT) resonance. We show that this approach achieves sufficient coherence to enable effective gray molasses cooling without the need for costly GHz electronics, significantly reducing the complexity and cost of experimental setups and represents a step toward more accessible cold atom technologies. A wave-function Monte Carlo analysis supports the experimental findings, offering insight into the cooling dynamics of this unconventional scheme

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Timothy Leese, Siobhan Patrick, Silvia Bergamini, Calum MacCormick. 2025-10-15. Efficient lambda-enhanced gray molasses using an EIT-based laser locking scheme. https://arxiv.org/abs/2510.13360

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