2005/10/28 by D. V. Averin, Dmitri V. Averin, Kristian Rabenstein +2
Computer Science · Physics and Astronomy · #Atomic and Subatomic Physics Research #Quantum Information and Cryptography #Quantum and electron transport phenomena #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.73.094504
12 pages, 5 figures
arxiv created 2005/10/28 · openalex publication_date 2006/03/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We suggest a magnetic flux detector that can be optimized with respect to the measurement back action, e.g., for the situation of quantum measurements. The detector is based on manipulation of ballistic motion of individual fluxons in a Josephson transmission line (JTL), with the output information contained in either probabilities of fluxon transmission and reflection, or time delay associated with the fluxon propagation through the JTL. We calculate the detector characteristics of the JTL and derive equations for conditional evolution of the measured system both in the transmission and reflection and the time-delay regimes. Combination of the quantum-limited detection with control over individual fluxons should make the JTL detector suitable for implementation of nontrivial quantum measurement strategies, including conditional measurements and feedback control schemes.