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arXiv · 1711.11347

Noninvasive Quantum Measurement of Arbitrary Operator Order by Engineered Non-Markovian Detectors

Johannes Bülte·Adam Bednorz·Christoph Bruder·Wolfgang Belzig
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Abstract

The development of solid-state quantum technologies requires the understanding of quantum measurements in interacting, non-isolated quantum systems. In general, a permanent coupling of detectors to a quantum system leads to memory effects that have to be taken into account in interpreting the measurement results. We analyze a generic setup of two detectors coupled to a quantum system and derive a compact formula in the weak-measurement limit that interpolates between an instantaneous (text-book type) and almost continuous - detector dynamics-dependent - measurement. A quantum memory effect that we term system-mediated detector-detector interaction is crucial to observe non-commuting observables simultaneously. Finally, we propose a mesoscopic double-dot detector setup in which the memory effect is tunable and that can be used to explore the transition to non-Markovian quantum measurements experimentally.

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Johannes Bülte, Adam Bednorz, Christoph Bruder, Wolfgang Belzig. 2017-11-30. Noninvasive Quantum Measurement of Arbitrary Operator Order by Engineered Non-Markovian Detectors. https://doi.org/10.1103/physrevlett.120.140407

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