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arXiv · 1804.08151

Quantum dynamics of a small symmetry breaking measurement device

H. C. Donker·H. De Raedt·M. I. Katsnelson
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Abstract

A quantum measuring instrument is constructed that utilises symmetry breaking to enhance a microscopic signal. The entire quantum system consists of a system-apparatus-environment triad that is composed of a small set of spin-1/2 particles. The apparatus is a ferromagnet that measures the $z$-component of a single spin. A full quantum many-body calculation allows for a careful examination of the loss of phase coherence, the formation and amplification of system-apparatus correlations, the irreversibility of registration, the fault tolerance, and the bias of the device.

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H. C. Donker, H. De Raedt, M. I. Katsnelson. 2018-04-22. Quantum dynamics of a small symmetry breaking measurement device. https://doi.org/10.1016/j.aop.2018.07.010

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