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arXiv · 1103.2803

Reconstructing the relaxation dynamics induced by an unknown heat bath

Jochen Rau
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Abstract

In quantum state tomography, one potential source of error is uncontrolled contact of the system with a heat bath whose detailed properties are not known, and whose impact on the system moreover varies between different runs of the experiment. Precisely these variations provide a handle for reconstructing the system's effective relaxation dynamics. I propose a pertinent estimation scheme which is based on a steepest-descent ansatz and maximum likelihood. After reconstructing the relaxation dynamics, the original quantum state of the system can be constrained to a curve in state space.

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Jochen Rau. 2011-03-14. Reconstructing the relaxation dynamics induced by an unknown heat bath. https://doi.org/10.1016/j.physleta.2011.12.007

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