MAGNETIC READ USING (FePt)100-XCuX AS PERMANENT MAGNET MATERIAL

摘要

A magnetic structure (130, 130’, 130’’) including a first layer of hard magnetic material (132) which has a magnetization that is substantially fixed in a first magnetization direction, a second layer of ferromagnetic material (136) which has a magnetization that is substantially rotatable, a nonmagnetic layer (134, 134’) provided between the first hard magnetic (132) and second ferromagnetic (136) layers, and a hard magnetic material element (34, 36, 74, 76) which has a magnetization that is substantially fixed in a second magnetization direction. The hard magnetic material element (34, 36, 74, 76) is magnetically coupled to the second ferromagnetic layer (136) and biases the second ferromagnetic layer (136) such that its magnetization is biased to lie in the second magnetization direction. Either the first hard magnetic layer (132) or the hard magnetic material element (34, 36, 74, 76) includes an FePtCu alloy. In one form, the FePtCu alloy includes the alloy (FePt)100-xCux and, in a further form, the variable x is equal to five.