Commensurate Quantum Oscillations in Coupled Qubits

TL;DR

This paper demonstrates how commensurate quantum oscillations in coupled qubits can be exploited to implement high-fidelity CNOT gates, with tunable parameters enabling robust quantum gate operations.

Contribution

It introduces a method to achieve CNOT gates via commensurate oscillations in coupled qubits, applicable across different coupling strengths and qubit energies.

Findings

CNOT gate operation is possible through commensurate oscillations.

High fidelity CNOT gates can be achieved by tuning the oscillating field.

Gate operation is robust for both weak and strong coupling regimes.

Abstract

We study the coupled-qubit oscillation driven by an oscillating field. When the period of the non-resonant mode is commensurate with that of the resonant mode of the Rabi oscillation, we show that the controlled-NOT (CNOT) gate operation can be demonstrated. For a weak coupling the CNOT gate operation is achievable by the commensurate oscillations, while for a sufficiently strong coupling it can be done for arbitrary parameter values. By finely tuning the amplitude of oscillating field it is shown that the high fidelity of the CNOT gate can be obtained for any fixed coupling strength and qubit energy gap in experiments.