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arXiv · 2309.10192

Geometric Ramsey Interferometry with a Tripod Scheme

Chetan Sriram Madasu·Ketan Damji Rathod·Chang Chi Kwong·David Wilkowski
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Abstract

Ramsey interferometry is a key technique for precision spectroscopy and to probe the coherence of quantum systems. Typically, an interferometer is constructed using two quantum states and involves a time-dependent interaction with two short resonant electromagnetic pulses. Here, we explore a different type of Ramsey interferometer where we perform quantum state manipulations by geometrical means, eliminating the temporal dependence of the interaction. We use a resonant tripod scheme in ultracold strontium atoms where the interferometric operation is restricted to a two-dimensional dark-state subspace in the dressed-state picture. The observed interferometric phase accumulation is due to an effective geometric scalar term in the dark-state subspace, which remarkably does not vanish during the free evolution time when the light-matter interaction is turned off. This study opens the door for more robust interferometers operating on multiple input-output ports.

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Chetan Sriram Madasu, Ketan Damji Rathod, Chang Chi Kwong, David Wilkowski. 2023-09-18. Geometric Ramsey Interferometry with a Tripod Scheme. https://doi.org/10.1103/physrevapplied.21.l051001

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