Encoded State Transfer: Beyond the Uniform Chain

TL;DR

This paper extends a previous method for perfect quantum state transfer by applying it to arbitrary spin chains and networks, providing guarantees for the existence of solutions and broadening its applicability.

Contribution

It generalizes the encoded state transfer technique to diverse spin systems and coupled networks, ensuring solution existence beyond uniform chains.

Findings

Applicable to arbitrary spin chains and networks

Guarantees on the existence of solutions

Broadens the scope of perfect quantum state transfer

Abstract

In a recent work (arXiv:2207.01954), we showed that a uniformly coupled chain could be symmetrically extended by engineered spin chains in such a way that we could choose part of the spectrum of the overall system. When combined with an encoding that avoids the uncontrolled eigenvalues, this resulted in the possibility of achieving a range of tasks such as perfect quantum state transfer. In this paper, we apply the same strategy to a much broader range of initial systems - arbitrary chains, and even coupled networks of spins - while providing guarantees on the existence of solutions.