Characterisation of a quantum bus between two driven qubits

• URL: http://arxiv.org/abs/2503.18772v2
• Date: Mon, 14 Apr 2025 14:25:23 GMT
• Title: Characterisation of a quantum bus between two driven qubits
• Authors: Alberto Hijano, Henri Lyyra, Juha T. Muhonen, Tero T. Heikkilä,
• Abstract summary: We use driven qubits coupled to a harmonic oscillator to implement a $sqrtimathrmSWAP$-gate.<n>We analyze a qubit readout mechanism based on the detection of a shift of the harmonic oscillator's resonance frequency.<n>Our findings guide the implementation of high-fidelity quantum gates in experimental setups.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We investigate the use of driven qubits coupled to a harmonic oscillator to implement a $\sqrt{i\mathrm{SWAP}}$-gate. By dressing the qubits through an external driving field, the qubits and the harmonic oscillator can be selectively coupled, leading to effective qubit-qubit interactions. We analyze a qubit readout mechanism based on the detection of a shift of the harmonic oscillator's resonance frequency, and demonstrate that when coupled to low-frequency resonators, dressed qubits provide a more robust readout than bare qubits in the presence of damping and thermal effects. Furthermore, we study the impact of various system parameters on the fidelity of the two-qubit gate, identifying an optimal range for quantum computation. Our findings guide the implementation of high-fidelity quantum gates in experimental setups, for example those employing nanoscale mechanical resonators.

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