Decoherence in Josephson vortex quantum bits: Long-Josephson-junction approach to a two-state system
Ju H. Kim, Ramesh P. Dhungana, Kee-Su Park
DOI 10.1103/PhysRevB.73.214506 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
We investigated decoherence of a Josephson vortex quantum bit (qubit) in dissipative and noisy environment. As the Josephson vortex qubit (JVQ) is fabricated by using a long Josephson junction (LJJ), we use the perturbed sine-Gordon equation to describe the phase dynamics representing a two-state system and estimate the effects of quasiparticle dissipation and weakly fluctuating critical and bias currents on the relaxation time T1 and on the dephasing time Tϕ. We show that the critical current fluctuation does not contribute to dephasing of the qubit in the lowest order approximation. Modeling the weak current variation from magnetic field fluctuations in the LJJ by using the Gaussian colored noise with long correlation time, we show that the coherence time T2 is limited by the low frequency current noise at very low temperatures. Also, we show that a ultra-long coherence time may be obtained from the JVQ by using experimentally accessible value of physical parameters.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| Nb-AlOx-Nb Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | — | Pressure not reported | unknown |
Similar papers
Instability of a rectangular vortex lattice in a stack of two long Josephson junctions
similarity 0.95A. V. Chiginev & V. V. Kurin
Source status unknown — claims are unverified
Controllable plasma energy bands in a one-dimensional crystal of fractional Josephson vortices
similarity 0.94H. Susanto et al.
Source status unknown — claims are unverified
Quantum noise in the Josephson charge qubit
similarity 0.91O. Astafiev et al. · 2004 · arXiv:cond-mat/0411216
Source status unknown — claims are unverified
Anomalous Josephson Current in Junctions with Spin Polarizing Quantum Point Contacts
similarity 0.90A. A. Reynoso et al.
Source status unknown — claims are unverified
Synchronized dynamics of Josephson vortices in artificial stacks of SNS Josephson junctions under both dc and ac bias currents
similarity 0.90G. R. Berdiyorov et al.
Source status unknown — claims are unverified
Decoherence of coupled Josephson charge qubits due to partially correlated low-frequency noise
similarity 0.90Yong Hu et al.
Source status unknown — claims are unverified