High Fidelity Quantum Control in a Quadruple Quantum Dot Device

In recent years, high fidelity single-qubit and two-qubit gates have been demonstrated for several different quantum processors based on lithographically defined quantum dot devices^[1][2][3][4]. Here we report another demonstration of high-fidelity single qubit operation with all single-qubit primitive gates approaching 99.99% fidelity as measured by Clifford randomized benchmarking. In this talk we will focus on the mitigation of severe switching noise through rapid automated recalibration of microwave control pulses. We will also discuss our recent efforts towards overcoming switching noise in the demonstration of high-fidelity two-qubit gates through tailored automated tune-up routines.

 

[1]Philips, S.G.J. et al. Universal control of a six-qubit quantum processor in silicon. Nature 609, 919–924 (2022)

[2]Mills, A., et al. Two-qubit silicon quantum processor with operation fidelity exceeding 99%.Sci. Adv.8,eabn5130 (2022)

[3]Yoneda, J., et al. A quantum-dot spin qubit with coherence limited by charge noise and fidelity higher than 99.9%. Nature Nanotech 13, 102–106 (2018).

[4]G. Burkhard et al., Rev. Mod. Phys. 95, 025003 (2023)