Tunable coupling of qubits: nonadiabatic corrections

Abstract

We analyze the coupling of qubits mediated by a tunable and fast element beyond the adiabatic approximation. The nonadiabatic corrections are important and even dominant in parts of the relevant parameter range. As an example, we consider the tunable capacitive coupling between two charge qubits mediated by a gated Josephson junction, as suggested by Averin and Bruder. The nonadiabatic, inductive contribution persists when the capacitive coupling is tuned to zero. On the other hand, the total coupling can be turned off (in the rotating wave approximation) if the qubits are operated at symmetry points.

7 pages, 2 figures, accepted in Europhysics Letters

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Cited by in corpus (17)

• Non-adiabatic processes in Majorana qubit systems
• Interqubit coupling mediated by a high-excitation-energy quantum object
• Geometrical spin dephasing in quantum dots
• Long-range coupling and scalable architecture for superconducting flux qubits
• Tunable inductive coupling of superconducting qubits in the strongly nonlinear regime
• Analysis of a tuneable coupler for superconducting phase qubits
• Selective darkening of degenerate transitions for implementing quantum controlled-NOT gates
• Tunable coupling between three qubits as a building block for a superconducting quantum computer
• Superconducting Circuit Architecture for Digital-Analog Quantum Computing
• Effective Hamiltonians for interacting superconducting qubits -- local basis reduction and the Schrieffer-Wolff transformation
• Charge solitons and their dynamical mass in 1-D arrays of Josephson junctions
• Stabilization of Qubit Relaxation Rates by Frequency Modulation
• Spin dephasing due to a random Berry phase
• Quantum phase transition of nonlocal Ising chain with transverse field in a resonator
• Theory of small charge solitons in one-dimensional arrays of Josephson junctions
• Quantum computation at the edge of a disordered Kitaev honeycomb lattice
• Emergence of a negative charging energy in a metallic dot capacitively coupled to a superconducting island