Competing interactions and spin-vector chirality in spin chains

摘要

Studies of competing orders in one-dimensional magnetic chains have attracted considerable attention in recent years, as the presence of distant-neighbor Heisenberg interactions is found to allow interesting quantum phase transitions. We investigate here the role of spin-orbit effects by considering spin-1/2 chains in the presence of both collinear and noncollinear interactions. By employing exact diagonalization and density matrix renormalization group calculations we investigate the rich phase diagram of this system. We find transitions from collinear to transverse magnetic correlated order as the strength of the noncollinear coupling increases, accompanied by a jump in the vector spin chirality order parameter of the system. This shows that tuning interactions allows control of the onset of sizable vector spin chirality in a system, which may be used to transmit information down the chain. We investigate the characteristic structure of the distinct phases and explore their possible physical implementation in different materials systems.