2013/10/31 by F. Chiarello, Samuele Spilla, S. Spilla +7 · 1 citation
Chemistry · Computer Science · Physics and Astronomy · #Biology #Charge qubit #Chemistry #Coherence (philosophical gambling strategy) #Degenerate energy levels #Flux (metallurgy) #Flux qubit #Phase qubit #Physics #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum mechanics #Quantum tunnelling #Qubit #Spectroscopy and Quantum Chemical Studies #Squid #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1103/physrevb.89.134506
published in Physical Review B 89(13) (American Physical Society) · 6 pages and 6 figures. The paper, as it is, has been accepted for publication on PRB on March 2014
arxiv created 2014/03/12 · openalex publication_date 2014/04/11 · arxiv updated 2015/06/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
By quickly modifying the shape of the effective potential of a double SQUID flux qubit from a single-well to a double-well condition, we experimentally observe an anomalous behavior, namely, an alternation of resonance peaks, in the probability to find the qubit in a given flux state. The occurrence of Landau-Zener transitions as well as resonant tunneling between degenerate levels in the two wells may be invoked to partially justify the experimental results. A quantum simulation of the time evolution of the system indeed suggests that the observed anomalous behavior can be imputable to quantum coherence effects. The interplay among all these mechanisms has a practical implication for quantum computing purposes, giving a direct measurement of the limits on the sweeping rates possible for a correct manipulation of the qubit state by means of fast flux pulses, avoiding transitions to noncomputational states.