Quantum Logic between Remote Quantum Registers

Abstract

We analyze two approaches to quantum state transfer in solid-state spin systems. First, we consider unpolarized spin-chains and extend previous analysis to various experimentally relevant imperfections, including quenched disorder, dynamical decoherence, and uncompensated long range coupling. In finite-length chains, the interplay between disorder-induced localization and decoherence yields a natural optimal channel fidelity, which we calculate. Long-range dipolar couplings induce a finite intrinsic lifetime for the mediating eigenmode; extensive numerical simulations of dipolar chains of lengths up to L=12 show remarkably high fidelity despite these decay processes. We further consider the extension of the protocol to bosonic systems of coupled oscillators. Second, we introduce a quantum mirror based architecture for universal quantum computing which exploits all of the spins in the system as potential qubits. While this dramatically increases the number of qubits available, the composite operations required to manipulate "dark" spin qubits significantly raise the error threshold for robust operation. Finally, as an example, we demonstrate that eigenmode-mediated state transfer can enable robust long-range logic between spatially separated Nitrogen-Vacancy registers in diamond; numerical simulations confirm that high fidelity gates are achievable even in the presence of moderate disorder.

15 pages, 10 figures

References in corpus (27)

• Non-Abelian Anyons and Topological Quantum Computation
• The Quantum Internet
• Quantum Computing
• Anderson Transitions
• Electromagnetically Induced Transparency and Slow Light with Optomechanics
• Coupling Superconducting Qubits via a Cavity Bus
• Coherent quantum state storage and transfer between two phase qubits via a resonant cavity
• Solid state quantum memory using the 31P nuclear spin
• Quantum computing with nearest neighbor interactions and error rates over 1%
• Chip-scale nanofabrication of single spins and spin arrays in diamond
• Coherent electronic transfer in quantum dot systems using adiabatic passage
• Spin Chains as Perfect Quantum State Mirrors
• Coherence Time of a Solid-State Nuclear Qubit
• Perfect state transfer on a spin-chain without state initialization
• Dynamics in a coupled-cavity array
• Perfect state transfer in long-range interacting spin chains
• Non-Perturbative Entangling Gates between Distant Qubits using Uniform Cold Atom Chains
• Simulations of Information Transport in Spin Chains
• 99%-fidelity ballistic quantum-state transfer through long uniform channels
• State Transfer and Spin Measurement
• Optimal quantum chain communication by end gates
• Quantum state transfer and time-dependent disorder in Quantum Chains
• Perfect function transfer and interference effects in interacting boson lattices
• Quantum Information Processing with Delocalized Qubits under Global Control
• Initializing an unmodulated spin chain to operate as a high quality quantum data-bus
• Quantum Data Bus in Dipolar Coupled Nuclear Spin Qubits
• High-probability quantum state transfer among nodes of an open XXZ spin chain

Cited by in corpus (3)

• Optimized dynamical control of state transfer through noisy spin chains
• Protected quantum-state transfer in decoherence-free subspaces
• Resource optimization for fault-tolerant quantum computing