English

Design of an RSFQ Control Circuit to Observe MQC on an rf-SQUID

Quantum Physics 2018-07-04 v1

Abstract

We believe that the best chance to observe macroscopic quantum coherence (MQC) in a rf-SQUID qubit is to use on-chip RSFQ digital circuits for preparing, evolving and reading out the qubit's quantum state. This approach allows experiments to be conducted on a very short time scale (sub-nanosecond) without the use of large bandwidth control lines that would couple environmental degrees of freedom to the qubit thus contributing to its decoherence. In this paper we present our design of a RSFQ digital control circuit for demonstrating MQC in a rf-SQUID. We assess some of the key practical issues in the circuit design including the achievement of the necessary flux bias stability. We present an "active" isolation structure to be used to increase coherence times. The structure decouples the SQUID from external degrees of freedom, and then couples it to the output measurement circuitry when required, all under the active control of RSFQ circuits. Research supported in part by ARO grant # DAAG55-98-1-0367.

Keywords

Cite

@article{arxiv.quant-ph/0102089,
  title  = {Design of an RSFQ Control Circuit to Observe MQC on an rf-SQUID},
  author = {Roberto C. Rey-de-Castro and Mark F. Bocko and Andrea M. Herr and Cesar A. Mancini and Marc J. Feldman},
  journal= {arXiv preprint arXiv:quant-ph/0102089},
  year   = {2018}
}

Comments

4 pages. More information and publications at http://www.ece.rochester.edu:8080/users/sde/research/publications/index.html