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arXiv · quant-ph/9908054

Effect of the measurement on the decay rate of a quantum system

Brahim Elattari·S. A. Gurvitz
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Abstract

We investigated the electron tunneling out of a quantum dot in the presence of a continuous monitoring by a detector. It is shown that the Schrödinger equation for the whole system can be reduced to new Bloch-type rate equations describing the time-development of the detector and the measured system at once. Using these equations we find that the continuous measurement of the unstable system does not affect its exponential decay, $\exp (-Γt)$, contrary to expectations based on the Quantum Zeno effect . However, the width of the energy distribution of the tunneling electron is no more $Γ$, but increases due to the decoherence, generated by the detector.

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Brahim Elattari, S. A. Gurvitz. 2000-01-02. Effect of the measurement on the decay rate of a quantum system. https://doi.org/10.1103/physrevlett.84.2047

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