Filters
Results 1 - 1 of 1
Results 1 - 1 of 1.
Search took: 0.021 seconds
Atalaya, Juan; Hacohen-Gourgy, Shay; Siddiqi, Irfan
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Funding organisation: USDOE Office of Science - SC (United States)2019
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Funding organisation: USDOE Office of Science - SC (United States)2019
AbstractAbstract
[en] Here, e ponder the effect of phase backaction on the correlator 〈I(t)I(t+τ)〉 for the output signal I(t) from continuous measurement of a qubit. We demonstrate that the interplay between informational and phase backactions in the presence of Rabi oscillations can lead to the correlator becoming larger than 1, even though |〈I〉|≤1. The correlators can be calculated using the generalized "collapse recipe," which we validate using the quantum Bayesian formalism. Moreover, he recipe can be generalized to the case of multitime correlators and arbitrary number of detectors, measuring non-commuting qubit observables. The theory agrees well with experimental results for continuous measurement of a transmon qubit. The experimental correlator exceeds the bound of 1 for a sufficiently large angle between the amplified and informational quadratures, causing the phase backaction. The demonstrated effect can be used to calibrate the quadrature misalignment.
Primary Subject
Source
OSTIID--1572818; AC02-05CH11231; Available from https://www.osti.gov/servlets/purl/1572818; DOE Accepted Manuscript full text, or the publishers Best Available Version will be available free of charge after the embargo period; arXiv:1910.08638
Record Type
Journal Article
Journal
Physical Review Letters; ISSN 0031-9007; ; v. 122(22); vp
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue