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arXiv · 1409.0958

Past quantum state analysis of the photon number evolution in a cavity

Théo Rybarczyk·Stefan Gerlich·Bruno Peaudecerf·Mariane Penasa·Brian Julsgaard·Klaus Moelmer·Sébastien Gleyzes·Michel Brune·Jean-Michel Raimond·Serge Haroche·Igor Dotsenko
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Abstract

A quantum system can be monitored through repeated interactions with meters, followed by their detection. The state of the system at time t is thus conditioned on the information obtained until that time. More insight in the state dynamics is provided, however, by the past quantum state (PQS) [S. Gammelmark et al. Phys. Rev. Lett. 111, 160401 (2013)]. It relies on all aspects of the system evolution which are recorded in the past and in the future of t. Using PQS analysis for the quantum non-demolition photon number counting in a cavity, we can reveal information hidden in the standard approach and resolve a wider range of number states. This experiment demonstrates the strong potential of PQS analysis.

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Théo Rybarczyk, Stefan Gerlich, Bruno Peaudecerf, Mariane Penasa, Brian Julsgaard, Klaus Moelmer, Sébastien Gleyzes, Michel Brune, Jean-Michel Raimond, Serge Haroche, Igor Dotsenko. 2014-09-03. Past quantum state analysis of the photon number evolution in a cavity. https://arxiv.org/abs/1409.0958

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