A Simulation Methodology for Superconducting Qubit Readout Fidelity

TL;DR

This paper presents a simulation methodology using Matlab and Ansys HFSS to predict and optimize superconducting qubit readout fidelity, aiding in the design of more efficient quantum computing systems.

Contribution

It introduces a co-optimization simulation approach for superconducting qubit readout fidelity based on actual system parameters and experimental calibration.

Findings

High fidelity maintained with 7dB power reduction

Readout pulse width can be reduced by 40% without losing fidelity

Simulation results closely match experimental data

Abstract

Qubit readout is a critical part of any quantum computer including the superconducting-qubit-based one. The readout fidelity is affected by the readout pulse width, readout pulse energy, resonator design, qubit design, qubit-resonator coupling, and the noise generated along the readout path. It is thus important to model and predict the fidelity based on various design parameters along the readout path. In this work, a simulation methodology for superconducting qubit readout fidelity is proposed and implemented using Matlab and Ansys HFSS to allow the co-optimization in the readout path. As an example, parameters are taken from an actual superconducting-qubit-based quantum computer and the simulation is calibrated to one experimental point. It is then used to predict the readout error of the system as a function of readout pulse width and power and the results match the experiment well. It is found that the system can still maintain high fidelity even if the input power is reduced by 7dB or if the readout pulse width is 40% narrower. This can be used to guide the design and optimization of a superconducting qubit readout system.