Automatic Qubit Characterization and Gate Optimization with QubiC

Citations Over TimeTop 20% of 2022 papers

Abstract

As the size and complexity of a quantum computer increases, quantum bit (qubit) characterization and gate optimization become complex and time-consuming tasks. Current calibration techniques require complicated and verbose measurements to tune up qubits and gates, which cannot easily expand to the large-scale quantum systems. We develop a concise and automatic calibration protocol to characterize qubits and optimize gates using QubiC , which is an open source FPGA (field-programmable gate array)-based control and measurement system for superconducting quantum information processors. We propose multi-dimensional loss-based optimization of single-qubit gates and full XY-plane measurement method for the two-qubit CNOT gate calibration. We demonstrate the QubiC automatic calibration protocols are capable of delivering high-fidelity gates on the state-of-the-art transmon-type processor operating at the Advanced Quantum Testbed at Lawrence Berkeley National Laboratory. The single-qubit and two-qubit Clifford gate infidelities measured by randomized benchmarking are of 4.9(1.1) × 10 -4 and 1.4(3) × 10 -2 , respectively.

Related Papers

• → Implementing a Ternary Decomposition of the Toffoli Gate on\n Fixed-FrequencyTransmon Qutrits(2021)20 cited
• → Asymmetry of CNOT gate operation in superconducting transmon quantum processors using cross-resonance entangling(2020)2 cited
• → Implementing a Ternary Decomposition of the Toffoli Gate on Fixed-FrequencyTransmon Qutrits(2021)1 cited