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arXiv · 1211.2870

Quantum back-action in spinor condensate magnetometry

S. K. Steinke·S. Singh·P. Meystre·K. C. Schwab·M. Vengalattore
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Abstract

We provide a theoretical treatment of the quantum backaction of Larmor frequency measurements on a spinor Bose-Einstein condensate by an off-resonant light field. Two main results are presented; the first is a "quantum jump" operator description that reflects the abrupt change in the spin state of the atoms when a single photon is counted at a photodiode. The second is the derivation of a conditional stochastic master equation relating the evolution of the condensate density matrix to the measurement record. We comment on applications of this formalism to metrology and many-body studies.

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S. K. Steinke, S. Singh, P. Meystre, K. C. Schwab, M. Vengalattore. 2012-11-13. Quantum back-action in spinor condensate magnetometry. https://doi.org/10.1103/physreva.88.063809

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