Long-range Antiferromagnetic Order in [MnTe/ZnTe] Superlattices
Abstract
Long range antiferromagnetic order has been found in epitaxially-grown superlattices of [(MnTe)_x/(ZnTe)_y] with thin ZnTe interlayers (e.g, y=3D4-6 monolayers) and MnTe layer thicknesses x =3D 10 and 20. Previous studies(T.M. Giebultowicz, P. Klosowski, N. Samarth, H. Luo, J. K. Furdyna, and J.J. Rhyne, Phys. Rev. B 48), 12817 (1993). of [MnTe/ZnTe] superlattices with thicker ZnTe interlayers (e.g., y=3D18) revealed antiferromagnetic order confined to single MnTe layers consistent with strong nearest-neighbor (NN) exchange and relatively weak higher-neighbor exchange. The thin ZnTe layer superlattices show an inphase antiferromagnetic interlayer coupling coherent across several bilayers with spin directions on adjacent MnTe layers determined by assuming "phantom" spins on the ZnTe layers with the same AFM order as the MnTe layers. As the temperature is raised, this ordering slowly transforms into an antiphase coupling with spin directions in alternate MnTe layers reversed from their low temperature structure. The magnetic scattered intensity from both co-existing phases vanishes at a common Neel temperature near 75 K.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1997
- Bibcode:
- 1997APS..MAR.N2206R