Efficient transfer of entanglement along a qubit chain in the presence of thermal fluctuations

TL;DR

This paper investigates the optimal conditions for transferring entanglement along a qubit chain using SWAP operations, considering environmental effects and drive-induced decoherence, to maximize fidelity.

Contribution

It identifies the existence of an optimal drive amplitude for entanglement transfer in open quantum systems, accounting for thermal fluctuations and decoherence effects.

Findings

Maximum fidelity at an optimal drive amplitude

Existence of an optimal transfer speed for entanglement

Environmental effects modeled with a fluctuation-regulated master equation

Abstract

Quantum communications require efficient implementations of quantum state transportation with high fidelity. Here, we consider the transport of entanglement along a chain of qubits. A series of SWAP operations involving successive pairs of qubits can transport entanglement along the chain. We report that the fidelity of the abovementioned gate has a maximum value corresponding to an optimum value of the drive amplitude in the presence of drive-induced decoherence. To incorporate environmental effect, we use a previously reported fluctuation-regulated quantum master equation [A. Chakrabarti and R. Bhattacharyya, Phys. Rev. A 97, 063837 (2018)]. The existence of an optimum drive amplitude implies that these series of SWAP operations on open quantum systems would have an optimal transfer speed of the entanglement.