Spin Canting
Some antiferromagnetic materials exhibit a non-zero magnetic moment at a temperature near absolute zero. This effect is ascribed to spin canting, a phenomenon through which spins are tilted by a small angle about their axis rather than being exactly co-parallel. Spin canting is due to two factors contrasting each other: isotropic exchange would align the spins exactly antiparallel, while antisymmetric exchange arising from relativistic effects ( spin–orbit coupling) would align the spins at 90° to each other. The net result is a small perturbation, the extent of which depends on the relative strength of these effects. This effect is observable in many materials such as hematite Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of . .... References {{reflist Magnetic ordering Spi ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]