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arXiv:2602.06230

Sawtooth wave adiabatic passage in a grating magneto-optical trap

Peter K. Elgee, Ananya Sitaram, Sara Ahanchi, Nikolai N. Klimov, Stephen P. Eckel, Gretchen K. Campbell, Daniel S. Barker

physics.atom-phquant-phSubmitted Feb 5, 2026• Announced Feb 9, 2026• 0 citations
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Abstract

We demonstrate sawtooth wave adiabatic passage (SWAP) in a grating magneto-optical trap (MOT) operating on the $^1$S$_0$ $\rightarrow$ $^3$P$_1$ transition of neutral $^{88}$Sr. From numerical simulations of SWAP using our laser beam geometry, we find that SWAP provides greater cooling than triangle wave frequency modulation despite the complex polarization environment of a grating MOT. The simulation is confirmed by our experimental results, where we demonstrate a factor of two improvement in transfer efficiency between our $^1$S$_0$ $\rightarrow$ $^1$P$_1$ grating MOT and our $^1$S$_0$ $\rightarrow$ $^3$P$_1$ grating MOT. We trap up to $3\times10^6$ $^{88}$Sr atoms in the $^1$S$_0$ $\rightarrow$ $^3$P$_1$ grating MOT, at an average temperature of 4.9 $μ$K with a lifetime of approximately 0.7 s. Our results show that SWAP is effective in non-orthogonal laser beam geometries, allowing greater duty cycles or higher atom number in sensors based on narrow-line grating MOTs.

Comments
9 pages, 7 figures

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