Effect of Decoherence for Gate Operations on a Superconducting Bosonic Qubit

TL;DR

This paper investigates how different loss mechanisms affect the fidelity of logical gate operations on superconducting bosonic qubits, providing a model to predict and optimize gate errors.

Contribution

It introduces a numerical model capturing loss channels in bosonic qubit gates, enabling better optimization to reduce errors.

Findings

Developed a gate error model for bosonic qubits.

Predicted achievable gate errors considering loss mechanisms.

Suggested optimization strategies for improved gate fidelity.

Abstract

High-quality-factor 3D cavities in superconducting circuits are ideal candidates for bosonic logical qubits as their fidelity is limited only by the low photon loss rate. However, the transmon qubits that are used to manipulate bosonic qubits result in the emergence of additional relaxation and dephasing channels. In this work, a numerical study is performed to elucidate the effect of the various loss channels on the performance of logical gates on a bosonic qubit. A gate error model is developed that encapsulates the loss mechanisms for arbitrary gate operations and predicts experimentally achievable gate errors for bosonic qubits. The insights gleaned from this study into loss mechanisms suggest more efficient optimization algorithms that could reduce gate errors on bosonic qubits.