Low‐temperature properties of a magnetic nanowire

Abstract

The cylindrical core–shell nanowire with an antiferromagnetic core and a ferromagnetic core described by the quantum Heisenberg spin model are studied by using linear spin‐wave theory and Green's function method. Considering the different symmetry of spins, we introduce two different Fourier transforms to spin‐deviate operators. We give the spectrum of the system, analyze the quantum fluctuations of spins at zero temperature, and discuss the low‐temperature behavior of the sublattice magnetization, internal energy and specific heat. It is found that the type of exchange interactions and spin special structure affect the magnetic properties of system very much, changing the magnetic structure of the system making the quantum fluctuation different, but cannot affect the thermal fluctuation dramatically.

Single‐Ion Anisotropy Effect on the Critical and Hysteresis Behaviors of a Mixed‐Spin (1, 3/2) Square Ising Nanowire

“…Due to the simplicity and practicality of Ising models, core-shell nanowires have the particularity of being represented by various single-and mixed-spin Ising systems and that can be solved approximately or numerically allowing comparison with experiment. Recently, several methods have been applied to the examination of these systems, such as effective field theory (EFT), [19][20][21] mean field theory (MFT), [22][23][24] Green's function method, [25] and Monte Carlo simulation (MCS). [24,[26][27][28][29] These studies are of great significance not only for the theoretical study of ferrimagnetic nanowires but also for experimental and practical applications.…”