Resonant two-qubit gates for fermionic simulations with spin qubits
Abstract
In gate-defined semiconductor spin qubits, the highly tunable Heisenberg exchange interaction is leveraged to implement fermionic two-qubit gates such as CZ and SWAP. However, the broader family of fermionic simulation (fSim) gates remains unexplored, and has the potential to enhance the performance of near-term quantum simulation algorithms. Here, we demonstrate a method to implement the fSim gate set in spin qubits using a single pulse combining baseband and resonant exchange drives. This approach minimizes gate duration and drive amplitude, mitigating decoherence and crosstalk. We validate its effectiveness by realizing a resonant iSWAP gate between two hole spins in germanium, achieving a fidelity of 93.8(5)% extracted with interleaved randomized benchmarking. Quantum process tomography confirms accurate gate calibration and identifies qubit decoherence as the dominant error source. Our results establish a practical route toward a versatile and efficient two-qubit gate set for spin-based quantum processors.
Cite
@article{arxiv.2507.13781,
title = {Resonant two-qubit gates for fermionic simulations with spin qubits},
author = {Konstantinos Tsoukalas and Alexei Orekhov and Bence Hetényi and Uwe von Lüpke and Jeth Arunseangroj and Inga Seidler and Lisa Sommer and Eoin G. Kelly and Leonardo Massai and Michele Aldeghi and Marta Pita-Vidal and Stephen W. Bedell and Stephan Paredes and Felix J. Schupp and Matthias Mergenthaler and Gian Salis and Andreas Fuhrer and Patrick Harvey-Collard},
journal= {arXiv preprint arXiv:2507.13781},
year = {2025}
}