Multiferroics

Spintronics involves the control and manipulation of the spin degrees of freedom in materials, impacting upon a range of solid state phenomena, including electron transport in metals and semiconductors and quantum spin states in molecular magnets and artificially structured quantum wells. Complex oxides are promising candidates for spintronics applications because of the large spin polarizations found in these materials, and also because of their unique transport properties, such as colossal magnetoresistive (CMR) phenomena that are related to metal-insulator transitions in the temperature-doping phase diagrams of these materials. Our research effort focuses on understanding the mechanisms underlying the physical processes that govern spin effects in complex oxides, as well as applying these ideas to the design and fabrication of novel spintronics devices. 

One recent example is the concept of a giant planar Hall effect memory device, which is based on the large anisotropic magnetoresistances and strong magnetic anisotropies exhibited by CMR materials [1-2]. This combination of attributes allows one to achieve magnetoresistive hysteresis loops that resemble the giant magnetoresistance curves of spin-valve structures. 

[1] Bason et al., Appl. Phys. Lett., 84: 2593, 2004
[2] Bason et al., J. Appl. Phys. 99:08R701, 2006