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arXiv · 2407.07579

Suppressing photon detection errors in nondeterministic state preparation

Csaba Czabán·Zoltán Kolarovszki·Márton Karácsony·Zoltán Zimborás
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Abstract

Photonic quantum computing has recently emerged as a promising candidate for fault-tolerant quantum computing by photonic qubits. These protocols make use of nondeterministic gates, enabling universal quantum computation. However, the suggested solutions heavily use particle number resolving detectors (PNRDs), which are experimentally hard to realize and are usually biased in practice. We investigate the possibility of suppressing such errors caused by such photodetector imperfections by adjusting the optimal beamsplitter and phaseshifter angles in the interferometer corresponding to nondeterministic gates. Moreover, we devise an optimization method for determining the adjusted angles, which may achieve higher output state fidelities while controlling the success probabilities of the nondeterministic gates.

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Csaba Czabán, Zoltán Kolarovszki, Márton Karácsony, Zoltán Zimborás. 2024-07-10. Suppressing photon detection errors in nondeterministic state preparation. https://arxiv.org/abs/2407.07579

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