Optimal tuning of solid-state quantum gates: A universal two-qubit gate

TL;DR

This paper introduces a method to optimize two-qubit quantum gates in solid-state devices, effectively mitigating inhomogeneous broadening and noise effects, thus enhancing gate fidelity.

Contribution

It provides a universal approach for tuning solid-state quantum gates to achieve high efficiency despite 1/f noise and noise interplay.

Findings

High-efficiency two-qubit gates are achievable with optimal coupling.

Entanglement degradation is quantified under realistic noise spectra.

The method is applicable to charge-phase $ oot{i-SWAP}$ gates.

Abstract

We present a general route to reduce inhomogeneous broadening in nanodevices due to 1/f noise. We apply this method to a universal two-qubit gate and demonstrate that for selected optimal couplings, a high-efficient gate can be implemented even in the presence of 1/f noise. Entanglement degradation due to interplay of 1/f and quantum noise is quantified via the concurrence. A charge-phase $\sqrt{{\rm i-SWAP}}$ gate for spectra extrapolated from single qubit experiments is analyzed.