Correlated flux noise and decoherence in two inductively coupled flux qubits

Abstract

We have studied decoherence in a system where two Josephson-junction flux qubits share a part of their superconducting loops and are inductively coupled. By tuning the flux bias condition, we control the sensitivities of the energy levels to flux noises in each qubit. The dephasing rate of the first excited state is enhanced or suppressed depending on the amplitudes and the signs of the sensitivities. We have quantified the $1/f$ flux noises and their correlations and found that the dominant contribution is by local fluctuations.

arXiv comment4 pages, 4 figures

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Cited by in corpus (20)

• 1/f noise: implications for solid-state quantum information
• Optimal control methods for fast time-varying Hamiltonians
• Spectroscopy of low-frequency noise and its temperature dependence in a superconducting qubit
• Flux qubit noise spectroscopy using Rabi oscillations under strong driving conditions
• A fluxonium-based artificial molecule with a tunable magnetic moment
• Pure dephasing in flux qubits due to flux noise with spectral density scaling as $1/f^{\alpha }$
• Noise correlations in a flux qubit with tunable tunnel coupling
• Evidence for temperature dependent spin-diffusion as a mechanism of intrinsic flux noise in SQUIDs
• Probing High Frequency Noise with Macroscopic Resonant Tunneling
• Flux-vector model of spin noise in superconducting circuits: Electron versus nuclear spins and role of phase transition
• Observation of Co-tunneling in Pairs of Coupled Flux Qubits
• Spin-echo entanglement protection from random telegraph noise
• Nonequilibrium Spin Noise and Noise of Susceptibility
• Charge and flux insensitive tunable superconducting qubit
• Fundamental limitations for measurements in quantum many-body systems
• Noise and microresonance of critical current in Josephson junction induced by Kondo trap states
• Efect of magnetic Gd impurities on superconductivity in MoGe films with different thickness and morphology
• NSQUID arrays as conveyers of quantum information
• Phenomenological noise model for superconducting qubits: two-state fluctuators and 1=f noise
• Direct spectrum analysis using a threshold detector with application to a superconducting circuit