Magnetic properties of a cylindrical Ising nanowire (or nanotube)

Abstract

Magnetic properties (phase diagram and magnetization) of a cylindrical Ising nanowire or nanotube are investigated by the use of the effective-field theory with correlations. Particular emphasis is given to the effects of the surface and its dilution on them. Much attention is paid to the thermal variation of the magnetization when the spins at the surface are coupled antiferromagnetically to the ferromagnetic core spins by the negative shell coupling. The effects of dilution at the surface, the surface exchange interaction, and the shell coupling on the magnetization profiles are investigated. We find a number of characteristic phenomena for them.

Dynamic phase transition properties and hysteretic behavior of a ferrimagnetic core–shell nanoparticle in the presence of a time dependent magnetic field

“…Namely, in the former group, equilibrium properties of these systems * Electronic address: hamza.polat@deu.edu.tr have been investigated by a variety of techniques such as mean field theory (MFT) [13,14,16,17], effectivefield theory (EFT) [15][16][17][18][19][20], Green functions formalism [21], variational cumulant expansion (VCE) [22,23] and Monte Carlo (MC) simulations [24][25][26][27][28][29][30][31]. Based on MC simulations, particular attention has been paid on the exchange bias (EB) effect in magnetic core-shell nanoparticles where the hysteresis loop exhibits a shift below the Néel temperature of the antiferromagnetic shell due to the exchange coupling on the interface region of ferromagnetic core and antiferromagnetic shell.…”

Magnetic Properties of a Transverse Ising Nanoparticle

“…. ) have been investigated by variety of techniques such as Monte Carlo simulations [10,11], mean field theory [12,13], effective field theory [14][15][16][17][18][19][20][21], Green's function [22], and cluster variation method [23]. In the recent works, the transverse Ising model has been applied to investigate materials with nanostructures [12,13].…”

Square Ising Nanowire on the Bethe Lattice

“…Then, this nanoparticle is connected to similar nanoparticles from above and below and so on to form a square Ising nanowire. Nanowires of different geometries have been studied to investigate its different aspects such as; the magnetic properties [1], initial susceptibility in addition to the reduced total magnetization [2], hysteresis behaviors [3], critical and compensation temperatures [4], phase diagrams and magnetizations in the case of surface dilution [5], and dynamic behaviors [6]. They were all investigated by the use of effective-field theory (EFT) with correlations.…”