Synopsis
Ferromagnetism is a form of magnetism that can be acquired in an external magnetic field and usually retained in its absence, so that ferromagnetic materials are used to make permanent magnets. A ferromagnetic material may therefore be said to have a high magnetic permeability and susceptibility (which depends upon temperature). Examples are iron, cobalt, nickel, and their alloys. Ultimately, ferromagnetism is caused by spinning electrons in the atoms of the material, which act as tiny weak magnets. They align parallel to each other within small regions of the material to form domains, or areas of stronger magnetism. In an unmagnetised material, the domains are aligned at random so there is no overall magnetic effect. If a magnetic field is applied to that material, the domains align to point in the same direction, producing a strong overall magnetic effect. Permanent magnetism arises if the domains remain aligned after the external field is removed. Ferromagnetic materials exhibit hysteresis. In 2004, it was discovered that a certain allotrope of carbon, nanofoam , exhibited ferromagnetism. The effect dissipates after a few hours at room temperature, but lasts longer at cold temperatures. The material is also a semiconductor. It is thought that other similarly formed materials, of boron and nitrogen, may also be ferromagnetic. This new book rings together leading research from throughout the world.

Table of contents

Ch. 1  Fully polarized states and decoherence by Marco Frasca

Ch. 2  Ferromagnetism in undoped manganites by Takashi Hotta

Ch. 3  Difference equations for correlation functions and form factors of the eight-vertex/XYZ model by Yas-Hiro Quano

Ch. 4  Basic properties of spin injection and transport in ferromagnetic/polymer systems by S. J. Xie and J. F. Ren and J. Y. Fu and K. H. Ahn and D. L. Smith and A. R. Bishop and A. Saxena

Ch. 5  Theory of spintronic transport in magnetic tunnel junctions by Gang Su

Ch. 6  Ferromagnetic phase transition in spinor Bose gases by Qiang Gu

Ch. 7  Giant oscillations of the density of states and the conductance in a ferromagnetic conductor coupled to two superconductors by A. Kadigrobov and R. I. Shekhter and M. Jonson

Ch. 8  The effect of geometry on the magneto-transport properties of insulating granular ferromagnets by A. Y. Dokow and A. Frydman

Ch. 9  Saturated and non-saturated ferromagnetism in the highly-correlated Hubbard model by V. Yu. Irkhin and A. V. Zarubin

Ch. 10     Phases and phase transitions in spin-triplet ferromagnetic superconductors by Diana V. Shopova and Dimo I. Uzunov

Ch. 11     Field and stress-tunable microwave composite materials based on ferromagnetic wires by D. P. Makhnovskiy and L. V. Panina

Ch. 12     Phase diagram and magnetic properties of ferromagnetic shape memory alloys Ni[subscript 2+x]Mn[subscript 1-x]Ga by V. V. Khovailo and V. D. Buchel'nikov and R. Z. Levitin and T. Takagi and A. N. Vasil'ev

Ch. 13     Spin polarized states in nuclear matter with Skyrme effective interaction by A. A. Isayev and J. Yang