Grover Search with Semiconductor Spin Qubits at Ambient Conditions

Sebastian Gemsheim; Fabian Klüpfel; Max Kneiß; Nicole Raatz; Tobias Herzig; Matthias Mendt; Evgeny Kreissig; Ulrike Rückert; Albrecht Hänel; Jan Meijer; Marius Grundmann

arXiv · 2609.13022

Grover Search with Semiconductor Spin Qubits at Ambient Conditions

Sebastian Gemsheim·Fabian Klüpfel·Max Kneiß·Nicole Raatz·Tobias Herzig·Matthias Mendt·Evgeny Kreissig·Ulrike Rückert·Albrecht Hänel·Jan Meijer·Marius Grundmann

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Abstract

Grover's algorithm is executed on a commercial quantum computer based on nitrogen-vacancy centers in diamond operating under ambient conditions, achieving fidelities up to $99.98\,\%$. Within a $N=8$ search space of three solid-state nuclear spin qubits, the measured success probabilities of finding a single or two marked states are $(77.3 \pm 3.4)\,\%$ and $(87.0 \pm 4.2)\,\%$, respectively. These values surpass published results for superconducting qubits or any quantum computer operating at room temperature. In addition, the paper also details the calibrated fidelities of the implemented universal gate set.

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Sebastian Gemsheim, Fabian Klüpfel, Max Kneiß, Nicole Raatz, Tobias Herzig, Matthias Mendt, Evgeny Kreissig, Ulrike Rückert, Albrecht Hänel, Jan Meijer, Marius Grundmann. 2026-09-18. Grover Search with Semiconductor Spin Qubits at Ambient Conditions. https://arxiv.org/abs/2609.13022

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