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arXiv · 2311.15762

Fidelity-dissipation relations in quantum gates

Tan Van Vu·Tomotaka Kuwahara·Keiji Saito
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Abstract

Accurate quantum computing relies on the precision of quantum gates. However, quantum gates in practice are generally affected by dissipative environments, which can significantly reduce their fidelity. In this study, we elucidate fundamental relations between the average fidelity of generic quantum gates and the dissipation that occurs during the computing processes. Considering scenarios in which a quantum gate is subject to Markovian environments, we rigorously derive fidelity-dissipation relations that hold for arbitrary operational times. Intriguingly, when the quantum gate undergoes thermal relaxation, the result can be used as a valuable tool for estimating dissipation through experimentally measurable fidelity, without requiring detailed knowledge of the dissipative structure. For the case of arbitrary environments, we uncover a trade-off relation between the average fidelity and energy dissipation, implying that these quantities cannot be large simultaneously. Our results unveil the computational limitations imposed by thermodynamics, shedding light on the profound connection between thermodynamics and quantum computing.

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Tan Van Vu, Tomotaka Kuwahara, Keiji Saito. 2023-11-27. Fidelity-dissipation relations in quantum gates. https://doi.org/10.1103/physrevresearch.6.033225

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