2012/04/28 by Simon Gustavsson, Fei Yan, Jonas Bylander +4 · 1 citation
Computer Science · Mathematics · Physics and Astronomy · #Charge qubit #Coherence (philosophical gambling strategy) #Coherence time #Computer science #Coupling (piping) #Decoupling (probability) #Dephasing #Dynamical decoupling #Flux qubit #Mathematics #Noise (video) #Phase qubit #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum computer #Quantum decoherence #Quantum mechanics #Qubit #Statistical physics #Topology (electrical circuits) #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1103/physrevlett.109.010502
arxiv created 2012/04/28 · openalex publication_date 2012/07/03 · arxiv updated 2015/06/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We implement dynamical decoupling techniques to mitigate noise and enhance the lifetime of an entangled state that is formed in a superconducting flux qubit coupled to a microscopic two-level system. By rapidly changing the qubit's transition frequency relative to the two-level system, we realize a refocusing pulse that reduces dephasing due to fluctuations in the transition frequencies, thereby improving the coherence time of the entangled state. The coupling coherence is further enhanced when applying multiple refocusing pulses, in agreement with our 1/f noise model. The results are applicable to any two-qubit system with transverse coupling and they highlight the potential of decoupling techniques for improving two-qubit gate fidelities, an essential prerequisite for implementing fault-tolerant quantum computing.