Fast and controllable topological excitation transfers in hybrid magnon-photon systems

Hybridized magnonic-photonic systems are key components for future information-processing technologies such as storage, manipulation, or conversion of data in the quantum regime owing to its ability to achieve collective excitation of spin waves and excellent properties of low damping rate, high spin density, and highly tunable excitations. We propose to realize fast and controllable topological single- and multiexcitation quantum state transfers (QSTs) through a magnon-circuit-QED chain. Various time-dependent magnon-photon and photon-photon couplings are tailored via the Kerr nonlinearity of the magnons and superconducting quantum interference devices, which are implemented fast magnon-magnon excitation transfers by mapping the system to a Su-Schrieffer-Heeger model. We analytically derive the edge state of the system, qualitatively explain the mechanism of fast QST, and numerically show the robustness of QST against on-site potential defects, the fluctuation of couplings, and losses of the system. Furthermore, when larger on-site defects are added to different types of lattice sites in the two ends, alternative single-excitation controllable magnon-photon, photon-magnon, and photon-photon transfers are also accessible. Our work opens up prospects for realizing a fast and controllable quantum channel in magnon-circuit-QED system and for facilitating further applications of topological matter in robust quantum information processing in magnonics and photonics.