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arXiv · 1007.5493

Monitoring Entanglement Evolution and Collective Quantum Dynamics

Georg M. Reuther·David Zueco·Peter Hänggi·Sigmund Kohler
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Abstract

We generalize a recently developed scheme for monitoring coherent quantum dynamics with good time-resolution and low backaction [Reuther et al., Phys. Rev. Lett. 102, 033602 (2009)] to the case of more complex quantum dynamics of one or several qubits. The underlying idea is to measure with lock-in techniques the response of the quantum system to a high-frequency ac field. We demonstrate that this scheme also allows one to observe quantum dynamics with many frequency scales, such as that of a qubit undergoing Landau-Zener transitions. Moreover, we propose how to measure the entanglement between two qubits as well as the collective dynamics of qubit arrays.

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Georg M. Reuther, David Zueco, Peter Hänggi, Sigmund Kohler. 2010-11-30. Monitoring Entanglement Evolution and Collective Quantum Dynamics. https://doi.org/10.1103/physrevb.83.014303

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