| AVS 66th International Symposium & Exhibition | |
| Magnetic Interfaces and Nanostructures Division | Thursday Sessions |
| Session MI+2D+AS+EM-ThM |
| Session: | Novel Magnetic Materials and Device Concept for Energy efficient Information Processing and Storage |
| Presenter: | Joseph Heremans, The Ohio State University |
| Authors: | J.P. Heremans, The Ohio State University B. He, The Ohio State University L. Zheng, The Ohio State University Y. Wang, The Ohio State University M.Q. Arguilla, The Ohio State University N.D. Cultrara, The Ohio State University M.R. Scudder, The Ohio State University J.E. Goldberger, The Ohio State University W. Windl, The Ohio State University |
| Correspondent: | Click to Email |
semiconductors that have p-type conduction along some crystallographic directions and n-type conduction along others due to a particular topology of their Fermi surface. The electrical and thermoelectric transport of one member of this class, NaSn2As2, will be presented. A second class of materials have similar transport properties due to different mechanisms: some, like Be and Cd, have Fermi surfaces that contain both electron and hole pockets that have partial thermopowers of opposite polarities, but very anisotropic mobilities, so that one carrier type dominates the total thermopower in one direction, and the other carrier type dominates the thermopower in the other direction. A new member of this class, the semimetal bismuth doped p-type with Sn, will be described in this talks as well. In practice, a third class of artificial materials made of separate layers of p-type and of n-type semiconductors can be made to have a similar behavior in transport as well; the last two classes are called (pxn)-materials.
The electrical conductivity and thermopower tensors in goniopolar and (pxn) materials can be made to have off-diagonal components, which cause exciting new properties like zero-field Hall and Nernst-Ettingshausen effects. These materials can be used in single-crystal transverse thermoelectrics.
[1] He, B. et al , Nat. Mater. (published online doi.org/10.1038/s41563-019-0309, 2019)
[2] Zhou, C. et al. Phys. Rev. Lett. 110, 227701 (2013).