Electronic transport of an extended Ising chain with competing thermal fluctuation and magnetic ordering

Abstract

In this study, we investigate the behavior of spin-dependent electronic transport in a magnetic nanowire with thermal random oriented moments, connected to two similar (anti-) ferromagnetic leads. The model is based on Green’s function technique within the nearest neighbor tight-binding approach in the framework of canonical ensemble. We analyze the electronic transmission and its variance in different ordered and disordered regimes at a finite temperature in an external magnetic field. The results indicate that at nonzero temperatures, thermal fluctuation of moment orientations decreases the system’s electronic conductance, leading to a smooth conductance-energy relationship. Depending on temperature and external magnetic field values as well as Ising exchange interaction strength, the system can transit to an ordered phase. Additionally, the larger length of the interacting part affects the transmission coefficient and amplifies its variance. This study sheds light on the intricate interplay between temperature, magnetic field, and moment orientations in the context of spin-dependent electronic transport through magnetic nanowires, offering valuable insights into the usage of such systems.