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arXiv · 1801.02437

Quantum metrology beyond Heisenberg limit with entangled matter wave solitons

D. V. Tsarev·S. M. Arakelian·You-Lin Chuang·Ray-Kuang Lee·A. P. Alodjants
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Abstract

By considering matter wave bright solitons from weakly coupled Bose-Einstein condensates trapped in a double-well potential, we study the formation of macroscopic non-classical states, including Schrödinger-cat superposition states and maximally path entangled $N00N$-states. With these macroscopic states, we examine Mach-Zehnder interferometer in the context of parity measurements, in order to obtain Heisenberg limit accuracy for linear phase shift measurement. We reveal that the ratio between two-body scattering length and intra-well hopping parameter can be measured with the scaling beyond this limit by using nonlinear phase shift with interacting quantum solitons.

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D. V. Tsarev, S. M. Arakelian, You-Lin Chuang, Ray-Kuang Lee, A. P. Alodjants. 2018-01-08. Quantum metrology beyond Heisenberg limit with entangled matter wave solitons. https://doi.org/10.1364/oe.26.019583

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