Events

Graduate Program Events

<< Summer 2021 Fall 2021 Spring 2022 >>
Subscribe your calendar or receive email announcements of events
Correlated Charge Noise and Relaxation Errors in Superconducting Qubits
Date: Tuesday, September 21st
Time: 2:00 pm
Place: Zoom: https://uwmadison.zoom.us/j/92504329607?pwd=MGtOVm1NZEhUVW1TZ09RYUlCS0NEUT09
Speaker: Chris Wilen, Physics PhD Graduate Student
Abstract: A crucial requirement to the surface code is that errors cannot be correlated. Here, we characterize a superconducting multiqubit circuit and find that charge fluctuations are highly correlated on a length scale over 600~μm; moreover, discrete charge jumps are accompanied by a strong transient suppression of qubit energy relaxation time across the millimeter-scale chip. The resulting correlated errors are explained in terms of the charging event and phonon-mediated quasiparticle poisoning associated with absorption of gamma rays and cosmic-ray muons in the qubit substrate. Robust quantum error correction will require the development of mitigation strategies to protect multiqubit arrays from correlated errors due to particle impacts.
Host: Robert McDermott, faculty advisor
Add this event to your calendar