Expediting quantum state transfer through the long-range extended XY model

TL;DR

This paper demonstrates that long-range interactions in the extended XY model significantly improve quantum state transfer efficiency, fidelity, and speed compared to short-range models, with optimal performance at intermediate coordination numbers.

Contribution

It provides a detailed analysis of how long-range interactions enhance quantum state transfer, identifying optimal parameters and regimes for improved performance.

Findings

Long-range interactions increase transfer fidelity.

Intermediate coordination numbers optimize transfer speed.

LR interactions reduce minimum transfer time.

Abstract

Going beyond short-range interactions, we explore the role of long-range interactions in the extended XY model for transferring quantum states through evolution. In particular, employing a spin-1/2 chain with interactions decaying as a power law, we demonstrate that long-range (LR) interactions significantly enhance the efficiency of a quantum state transfer (QST) protocol, improving the achievable fidelity, mitigating its slow decline as compared with the nearest-neighbor setting, associated with increasing system-size. Our study identifies the LR regime as providing an optimal balance between interaction range and transfer efficiency, outperforming the protocol with the short-range interacting model. Our detailed analysis reveals the impact of system parameters, such as anisotropy, magnetic field strength, and coordination number, on QST dynamics. Specifically, we find that intermediate coordination numbers lead to a faster and more reliable state transfer, while extreme values diminish performance. Furthermore, we exhibit that the presence of LR interactions considerably reduces the minimum time required to achieve fidelity beyond the classical limit.