Robustness of spin-coupling distributions for perfect quantum state transfer

TL;DR

This paper investigates how different spin coupling configurations in quantum spin chains affect the robustness of perfect quantum state transfer, emphasizing the role of energy eigenstate localization in mitigating imperfections.

Contribution

It provides a comparative analysis of various spin coupling distributions, highlighting the importance of localization properties for robust quantum information transfer.

Findings

Localization properties influence robustness against perturbations

Certain coupling distributions are more resilient to imperfections

Energy eigenstate characteristics relate to transfer fidelity

Abstract

The transmission of quantum information between different parts of a quantum computer is of fundamental importance. Spin chains have been proposed as quantum channels for transferring information. Different configurations for the spin couplings were proposed in order to optimize the transfer. As imperfections in the creation of these specific spin-coupling distributions can never be completely avoided, it is important to find out which systems are optimally suited for information transfer by assessing their robustness against imperfections or disturbances. We analyze different spin coupling distributions of spin chain channels designed for perfect quantum state transfer. In particular, we study the transfer of an initial state from one end of the chain to the other end. We quantify the robustness of different coupling distributions against perturbations and we relate it to the properties of the energy eigenstates and eigenvalues. We find that the localization properties of the systems play an important role for robust quantum state transfer.