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arXiv · 1712.05002

Blue-detuned magneto-optical trap

K. N. Jarvis·J. A. Devlin·T. E. Wall·B. E. Sauer·M. R. Tarbutt
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Abstract

We present the properties and advantages of a new magneto-optical trap (MOT) where blue-detuned light drives `type-II' transitions that have dark ground states. Using $^{87}$Rb, we reach a radiation-pressure-limited density exceeding $10^{11}$cm$^{-3}$ and a temperature below 30$\mu$K. The phase-space density is higher than in normal atomic MOTs, and a million times higher than comparable red-detuned type-II MOTs, making it particularly attractive for molecular MOTs which rely on type-II transitions. The loss of atoms from the trap is dominated by ultracold collisions between Rb atoms. For typical trapping conditions, we measure a loss rate of $1.8(4)\times10^{-10}$cm$^{3}$s$^{-1}$.

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K. N. Jarvis, J. A. Devlin, T. E. Wall, B. E. Sauer, M. R. Tarbutt. 2017-12-13. Blue-detuned magneto-optical trap. https://doi.org/10.1103/physrevlett.120.083201

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