Antiresonance and interaction-induced localization in spin and qubit chains with defects

Abstract

We study a spin chain with an anisotropic XXZ coupling in an external field. Such a chain models several proposed types of a quantum computer. The chain contains a defect with a different on-site energy. The interaction between excitations is shown to lead to two-excitation states localized next to the defect. In a resonant situation scattering of excitations on each other might cause decay of an excitation localized on the defect. We find that destructive quantum interference suppresses this decay. Numerical results confirm the analytical predictions.

Updated version

References in corpus (8)

• Quantum state engineering with Josephson-junction devices
• Electron transport through double quantum dots
• Experimental realization of Shor's quantum factoring algorithm using nuclear magnetic resonance
• Quantum oscillations in two coupled charge qubits
• An all silicon quantum computer
• Control of Spin Dynamics of Excitons in Nanodots for Quantum Operations
• Qubits with electrons on liquid helium
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Cited by in corpus (8)

• Integrability of a disordered Heisenberg spin-1/2 chain
• Entanglement versus chaos in disordered spin chains
• Quantum Chaos, Delocalization, and Entanglement in Disordered Heisenberg Models
• Two-particle localization and antiresonance in disordered spin and qubit chains
• Effects of the interplay between interaction and disorder in bipartite entanglement
• Bethe ansatz description of edge-localization in the open-boundary XXZ spin chain
• Quantum interference-induced stability of repulsively bound pairs of excitations
• Decoherence of one-dimensional flying qubits due to their cross-talk and imperfections