An unshunted comparator as a device for quantum measurements

Author

Wulf, Michael ; Zhou, Xingxiang ; Habif, Jonathan L. ; Rott, Pavel ; Bocko, Mark F. ; Feldman, Marc J.

Author_Institution

Dept. of Phys. & Astron., Univ. of Rochester, NY, USA

Volume

13

Issue

2

fYear

2003

fDate

6/1/2003 12:00:00 AM

Firstpage

974

Lastpage

977

Abstract

The unshunted single-flux-quantum SFQ comparator is described for the first time. Its dynamic behavior is surprisingly similar to the familiar resistively-shunted SFQ comparator. For certain parameter ranges both junctions of the comparator may pulse at the same time to create a reflected anti-pulse. This phenomenon is utilized in a new SFQ comparator design with better coherence properties for qubit readout. Considerations of quantum noise for the unshunted SFQ comparator are discussed.

Keywords

comparators (circuits); quantum noise; readout electronics; superconducting device noise; superconducting integrated circuits; Josephson junction; anti-pulse reflection; coherence properties; quantum measurement; quantum noise; qubit readout; superconducting circuit; unshunted SFQ comparator; Current measurement; Extraterrestrial measurements; Foundries; Integrated circuit measurements; Josephson junctions; Magnetic field measurement; Physics; Pulse measurements; SQUIDs; Superconducting device noise;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2003.814117

Filename

1211768