Symposium Q: Magnetic Thin Films, Heterostructures, and Device Materials
Abstract
In Symposium Q on Magnetic Thin Films, Heterostructures, and Device Materials, spin-dependent tunneling junctions were presented, with a particular focus on Fe/MgO/Fe junctions. Tunneling magnetoresistance values in this system have recently attained up to 350% at room temperature, several times higher than those seen in any other materials system. High magnetoresistance values were presented experimentally, treated through ab initio models, and correlated with MgO barrier structure by in situ STM and XPs characterization. Prospects for incorporation into nonvolatile magnetic RAM devices were also reviewed. Among other highlights were possibilities for novel interactions of ferromagnetic layers with other functional material types; novel rectifying possibilities, predicted theoretically, for the integration of ferroelectric such as SrTiO3, in the tunnel barrier between metallic Co electrodes; unambiguous proof of electrical injection and detection of spin-polarized electrons from metallic ferromagnets through GaAs, through the Hanle effect; and all-oxide magnetic tunneling junctions based on NiMn2O4 barriers. Materials approaches to increasing subnanosecond switching speeds, critical for high-data-rate (>% GHz) information storage, were presented. It was shown that the damping constant for high-speed motion can be predicted from first principles only in layered structures; controlled in epitaxial Fe alloys, potentially reduced below the intrinsic value of pure Fe; correlated with the femtosecond demagnetization process; and understood microscopically through picosecond-scale time-resolved x-ray spectroscopy. Composition spread approaches for the discovery of high-frequency magnetic materials were also reviewed.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 22, 2007
- Accession Number
- ADA468427
Entities
People
- William Bailey
Organizations
- Materials Research Society