Nonlinear Tripartite Coupling of Single Electrons on Solid Neon with Magnons in a Hybrid Quantum System

Abstract: Coherent nonlinear tripartite interactions are critical for advancing quantum simulation and information processing in hybrid quantum systems, yet they remain experimentally challenging and still evade comprehensive exploration. Here, we predict a nonlinear tripartite coupling mechanism in a hybrid setup comprising a single electron trapped on a solid neon surface and a nearby micromagnet. The tripartite coupling here leverages the electron's intrinsic charge (motional) and spin degrees of freedom interacting with the magnon modes of the micromagnet. Thanks to the large spatial extent of the electron zero-point motion, we show that it is possible to obtain a tunable and strong spin-magnon-motion coupling at the single quantum level, with two phonons simultaneously interacting with a single spin and magnon excitation. This enables, for example, dissipative interactions between the electron's charge and spin degrees of freedom, permitting controlled phonon addition/subtraction in the electron's motional state and the preparation of steady-state non-Gaussian motional states. This protocol can be readily implemented with the well-developed techniques in electron traps and may open new avenues for general applications in quantum simulations and information processing based on strongly coupled hybrid quantum systems.