Robust quantum state transfer inspired by Dzyaloshinskii-Moriya interactions

Abstract

Quantum state transfer (QST) is a fundamental problem in quantum mechanics and is important for quantum information processing. In this paper we explore a fast, robust, and efficient QST in spin-based quantum dots. Differing from the usual method that only uses the exchange interactions to control the evolution of the spin system, here we treat the non-negligible Dzyaloshinskii-Moriya (DM) interactions that can be electrically and thermally controlled in quantum dots as an assisted driving to accelerate the population transfer. We demonstrate that the DM interactions are not an error source, but are beneficial for population evolution under certain condition because they can sufficiently eliminate the undesirable quantum transitions among adiabatic passages and strictly maintain the population evolution in a designed passage with high efficiency. We give a generic $N$-spin anisotropic Heisenberg spin model to describe the population evolution and take specific two- and three-spin systems as examples to demonstrate the advantages of the DM interactions for QST.