Inhomogeneous entanglement structure in monoaxial chiral ferromagnetic quantum spin chain

Abstract

Chiral magnets, characterized by inhomogeneous magnetic moment arrangements, have attracted significant attention recently due to their topological orders, such as magnetic skyrmion lattices and chiral soliton lattices. In this work, we investigate the entanglement entropy of \textit{quantum} chiral magnets and demonstrate that it reflects the inhomogeneous nature of the ground state. We perform numerical simulations of a one-dimensional monoaxial chiral ferromagnetic chain with Zeeman term using the density matrix renormalization group method. Our results show that the entanglement entropy exhibits oscillatory behavior, which can be tuned by varying the external magnetic field. Analysis of the local magnetization and spin chirality further confirms that these oscillations correspond to solitonic structures. Moreover, our findings suggest that the entanglement entropy can serve as a probe for detecting the vacuum structure, providing new insights into quantum correlations.