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Preserving Quantum States : A Super-Zeno Effect

Deepak Dhar·Lov K. Grover·Shasanka M. Roy
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Abstract

We construct an algorithm for suppressing the transitions of a quantum mechanical system, initially prepared in a subspace P of the full Hilbert space of the system, to outside this subspace by subjecting it to a sequence of unequally spaced short-duration pulses. Each pulse multiplies the amplitude of the vectors in the subspace by -1. The number of pulses required by the algorithm to limit the leakage probability to $ε$ in time $T$ increases as $T \exp[ \sqrt{\log(T^2/ε)}]$, compared to $T^2 ε^{-1}$ in the standard quantum Zeno effect.

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Deepak Dhar, Lov K. Grover, Shasanka M. Roy. 2006-03-10. Preserving Quantum States : A Super-Zeno Effect. https://arxiv.org/abs/quant-ph/0504070

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