# Quantum-Enhanced Sensing Based on Time Reversal of Nonlinear Dynamics.

@article{Linnemann2016QuantumEnhancedSB, title={Quantum-Enhanced Sensing Based on Time Reversal of Nonlinear Dynamics.}, author={Daniel Linnemann and Helmut Strobel and Wolfgang Muessel and Jonas Schulz and Robert J. Lewis-Swan and Karen V. Kheruntsyan and Markus K. Oberthaler}, journal={Physical review letters}, year={2016}, volume={117 1}, pages={ 013001 } }

We experimentally demonstrate a nonlinear detection scheme exploiting time-reversal dynamics that disentangles continuous variable entangled states for feasible readout. Spin-exchange dynamics of Bose-Einstein condensates is used as the nonlinear mechanism which not only generates entangled states but can also be time reversed by controlled phase imprinting. For demonstration of a quantum-enhanced measurement we construct an active atom SU(1,1) interferometer, where entangled state preparation…

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