Superconductivity at the oxide-insulator/KTaO3 interface and electric-field control of magnon spin current in Cr2O3
Changjiang Liu, Department of Physics, University of Buffalo
Abstract. — Oxide material system is an ideal playground for uncovering new physical phenomena owing to the strong interactions between electron spins, charges, and lattices. In this talk, I will first present the recent discovery of two-dimensional superconductivity at the oxide-insulator/KTaO3 (111) interfaces. The superconducting transition temperature Tc reaches 2.2 K, which is about one order of magnitude higher than that found in the widely studied LaAlO3/SrTiO3 system. Notably, this new interfacial superconductor shows some unusual properties, including crystallographic orientation dependent superconductivity and an in-plane transport anisotropy. If time permits, I will then discuss how thermally excited magnons can be used to probe individual magnetic sublattices in the antiferromagnetic insulator Cr2O3. I will also show that the magnon spin current can be further controlled by an electric field via the magnetoelectric coupling in this classical antiferromagnet.
Host: Shulei Zhang