Unsharp continuous measurement of a Bose-Einstein condensate: Full quantum state estimation and the transition to classicality
Unsharp continuous measurement of a Bose-Einstein condensate: Full quantum state estimation and the transition to classicality
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DOI：
10.1103/physreva.86.033624
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发表时间：
2012-06
影响因子：
2.9
通讯作者：
M. Hiller;M. Rehn;Francesco Petruccione;A. Buchleitner;T. Konrad
中科院分区：
文献类型：
--
作者：
M. Hiller;M. Rehn;Francesco Petruccione;A. Buchleitner;T. Konrad
We study a Bose-Einstein condensate (BEC) in a double-well potential subject to an unsharp continuous measurement of the atom number in one of the two wells. We investigate the back action of the measurement on the quantum dynamics and the viability to monitor the ensuing time evolution. For vanishing inter-atomic interactions, mainly the expectation values of the measured local observable can be inferred from the measurement record. Conversely, in the presence of moderate inter-atomic interactions, the entire many-body state --modified by the measurement-- is monitored with unit fidelity and, at the same time, the measurement effects a transition from quantum to mean-field (classical) behavior of the BEC. We show that this perfect state estimation is possible because the inter-atomic interactions enhance the information gained via the measurement.
