Accelerated adiabatic dynamics in a triangular spin cluster

Abstract

We propose a scheme of the fast forward of adiabatic spin dynamics in a triangular spin cluster. We settle the quasi-adiabatic spin dynamics (QASD) by adding the regularization terms to the original Hamiltonian and accelerate it with use of a large time-scaling factor which realizes QASD on shortened time scale. Assuming the candidate regularization Hamiltonian consisting of three-body interactions besides the pair-wise exchange interactions and magnetic field, we solved the regularization terms. These terms multiplied by the velocity function give rise to the statedependent counter-diabatic terms (CDTs) for each of adiabatic states. Our fast forward Hamiltonian proves to generate the plural number of state-dependent CDTs due to the driving three-body interactions. Applying this scheme to a simple transverse Ising model, we find 2 CDTs which contains both two-body and three body interaction. The driving two and three-body interaction in the fast-forward scheme guarantees the complete fidelity of accelerated states.