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arXiv · 2106.05155

Time scaling and quantum speed limit in non-Hermitian Hamiltonians

F. Impens·F. M. D'Angelis·F. A. Pinheiro·D. Guéry-Odelin
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Abstract

We report on a time scaling technique to enhance the performances of quantum protocols in non-Hermitian systems. The considered time scaling involves no extra-couplings and yields a significant enhancement of the quantum fidelity for a comparable amount of resources. We discuss the application of this technique to quantum state transfers in 2 and 3-level open quantum systems. We derive the quantum speed limit in a system governed by a non-Hermitian Hamiltonian. Interestingly, we show that, with an appropriate driving, the time-scaling technique preserves the optimality of the quantum speed with respect to the quantum speed limit while reducing significantly the damping of the quantum state norm.

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F. Impens, F. M. D'Angelis, F. A. Pinheiro, D. Guéry-Odelin. 2021-06-09. Time scaling and quantum speed limit in non-Hermitian Hamiltonians. https://doi.org/10.1103/physreva.104.052620

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