Optimal dynamics for quantum-state and entanglement transfer through homogeneous quantum wires

TL;DR

This paper demonstrates how to optimize quantum-state and entanglement transfer in homogeneous quantum wires by tuning endpoint couplings, providing a scalable and broadly applicable method without complex engineering.

Contribution

It introduces a general procedure to find the optimal coupling for quantum transfer in homogeneous wires and derives scaling laws relating coupling to wire length.

Findings

Optimal coupling values enhance transfer efficiency

Scaling laws relate wire length to coupling parameters

Method applies broadly without complex engineering

Abstract

It is shown that effective quantum-state and entanglement transfer can be obtained by inducing a coherent dynamics in quantum wires with homogeneous intrawire interactions. This goal is accomplished by tuning the coupling between the wire endpoints and the two qubits there attached, to an optimal value. A general procedure to determine such value is devised, and scaling laws between the optimal coupling and the length of the wire are found. The procedure is implemented in the case of a wire consisting of a spin-1/2 XY chain: results for the time dependence of the quantities which characterize quantum-state and entanglement transfer are found of extremely good quality and almost independent of the wire length. The present approach does not require `ad hoc' engineering of the intrawire interactions nor a specific initial pulse shaping, and can be applied to a vast class of quantum channels.