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arXiv · 1908.00443

Optimal Clock Speed of Single-Qubit Operations on Open Quantum Systems

Nilanjana Chanda·Rangeet Bhattacharyya
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Abstract

Efficient implementation of quantum algorithms requires single- or multi-qubit gates with high fidelity. In this report, we report that the fidelity of single-qubit gate operations on open quantum systems has a maximum value corresponding to an optimum value of the drive-amplitude in the presence of drive-induced decoherence. To show this, we use a previously reported fluctuation-regulated quantum master equation [Phys. Rev. A 97, 063837 (2018)]. The fidelity is found to be a function of the drive-induced dissipative terms as well as the relaxation terms arising from the qubit-environment coupling; as a result, it behaves non-monotonically with the drive-amplitude. The existence of an optimum drive-amplitude implies that the single-qubit operations on open quantum systems would have an optimal clock speed.

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Nilanjana Chanda, Rangeet Bhattacharyya. 2019-08-01. Optimal Clock Speed of Single-Qubit Operations on Open Quantum Systems. https://doi.org/10.1103/physreva.101.042326

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