Materials with Extraordinary Spin/Heat Coupling
Abstract
The discovery of a fundamentally new energy conversion process is a rare event. Ten years ago, experimentalists demonstrated a new thermodynamic effect where the flow of heat in a material generates a flow of electron spin, essentially a flow of magnetic moments. These observations took the name spin-Seebeck effect in analogy with the well-known coupling between heat and electricity that underlies theoperation of thermocouples and thermoelectric generators. The spin-Seebeck effect promised new avenues for manipulating magnetism, and a new approach for generating electrical power from a temperature difference. Theoretical understanding of the spin-Seebeck effect and related phenomena, collectively referred to as spin caloritronics, developed slowly. The community of scientists studying spin caloritronics effects consisted predominately of physicists from the field of magnetic devices who were less well-versed in measurement and understanding of heat transport. To accelerate progress in this emerging field, the MURI team formed in 2012 under the leadership of Professor Roberto Myers at Ohio State University and brought together experts in the physics of spin and heat transport in materials. The members of the MURI team experimentally discovered or theoretically predicted several of the key spin-heat conversion effects. The vision of the MURI team was to develop a fundamental understanding of spin-heat coupling in solids through coordinated research in theory, experiment, measurement science, and new materials. Before the MURI team was established, the conversion of heat to electrical power by the spin-Seebeck effect was known to be a three-stage process: i) generation of spin currents by temperature gradients; ii) transport of spin across an interface between a ferromagnetic insulator and a normal metal; and iii) conversion between spin and charge currents by the relativistic effects of spin-orbit coupling.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 06, 2020
- Accession Number
- AD1110604
Entities
People
- Roberto C. Myers
Organizations
- Ohio State University