Theory of Advanced Magnetic Materials
Grant-in-Aid for Overseas Scientific Survey.
|Allocation Type||Single-year Grants|
|Research Institution||Nagoya University|
INOUE Junichiro Nagoya Univ., School of Eng., Assoc.Prof., 工学部, 助教授 (60115532)
EDWARDS David m. Imperial College of London Univ., Dept.of Maths., Prof., 数学科, 教授
TOHYAMA Takami Mie Univ., Shool of Edu., Lecturer, 教育学部, 講師 (70237056)
ENOMOTO Yosihisa Nagoya Inst.of Tech., Lecturer, 工学部, 講師 (70194008)
OHTA Yukinori Nagoya Univ., School of Eng., Assist., 工学部, 助手 (70168954)
MAEKAWA Sadamichi Nagoya Univ., School of Eng., Prof., 工学部, 教授 (60005973)
|Project Period (FY)
Completed(Fiscal Year 1994)
|Keywords||Magnetic superlattices / Granular films / Mn-oxides / Giant magnetoresistance / Exchange coupling / Spin and change degrees of freedom|
Magnetic superlattices have recently attracted much attention as novel functional magnetic materials. Especially, the giant magnetoresistance is an interesting phenomenon where the spin and change degrees of freedom couple each other. These materials have high potential for technical applications and produce fundamental issues to be solved in the field of basic solid state physics as well. The purposes of the present joint research are to study the electronic structures, magnetic and transport properties of magnetic superlattices as well as other magnetic materials and to establish unified picture for the phenomena and give useful information to the material design of advanced magnetic materials. In this research we have investigated following four subjects ; the giant magnetoresistance in magnetic superlattices, giant magnetoresistance in granular alloy films, exchange coupling in the magnetic superlattice, and giant magnetoresistance in the Mn oxides.
1. The origin of the giant magnetoresistanecs between currents parallel and perpendicular to layr planes has been studied. The anisotropy of effective mass of electrons and 2-dimensional distribution of the randomness on interfaces have been shown to be crucial to the anisotropy of the magnetoresistance.
2. Effects of the shape of the magnetic grains on the magnetoresistance in the granular alloy films have been investigated.
3. Effects of the randomness on the interfaces of magnetic superlattices on the exchange coupling have been studied. It has been shown the magnitude and phase of the oscillation of the exchange coupling are affected by the randomness.
4. It has been pointed out that the Hund coupling governs the giant magnetoresistance in the perovskite Mn oxides.
Research Output (18results)