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arXiv · 2012.07216

Nuclear spin squeezing in Helium-3 by continuous quantum nondemolition measurement

Alan Serafin·Matteo Fadel·Philipp Treutlein·Alice Sinatra
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Abstract

We propose a technique to control the macroscopic collective nuclear spin of a Helium-3 vapor in the quantum regime using light. The scheme relies on metastability exchange collisions to mediate interactions between optically accessible metastable states and the ground-state nuclear spin, giving rise to an effective nuclear spin-light quantum nondemolition interaction of the Faraday form. Our technique enables measurement-based quantum control of nuclear spins, such as the preparation of spin-squeezed states. This, combined with the day-long coherence time of nuclear spin states in Helium-3, opens the possibility for a number of applications in quantum technology.

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Alan Serafin, Matteo Fadel, Philipp Treutlein, Alice Sinatra. 2020-12-14. Nuclear spin squeezing in Helium-3 by continuous quantum nondemolition measurement. https://doi.org/10.1103/physrevlett.127.013601

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