AVS 64th International Symposium & Exhibition
    Electronic Materials and Photonics Division Monday Sessions
       Session EM+MI+TF-MoM

Invited Paper EM+MI+TF-MoM3
Topology, Magnetism, and Superconductivity in Ternary Half-Heusler Semimetals

Monday, October 30, 2017, 9:00 am, Room 14

Session: Growth, Electronic, and Magnetic Properties of Heusler Compounds
Presenter: Johnpierre Paglione, University of Maryland, College Park
Correspondent: Click to Email
In materials with non-centrosymmetric crystallographic structures, it has long been known that the lack of inversion symmetry can give rise to odd-parity spin-triplet pairing states. We report superconductivity and magnetism in a new family of topological semimetals, the ternary half Heusler compounds RPtBi and RPdBi (R : rare earth). In this series, tuning of the rare earth f-electron component allows for simultaneous control of both lattice density via lanthanide contraction, as well as the strength of magnetic interaction via de Gennes scaling, allowing for a unique tuning of both the normal state band inversion strength, superconducting pairing and magnetically ordered ground states. Antiferromagnetism with ordering vector (0.5,0.5,0.5) occurs below a Néel temperature that scales with de Gennes factor, while a superconducting transition is simultaneously linearly suppressed. With superconductivity appearing in a system with non-centrosymmetric crystallographic symmetry as well as p-orbital derived spin-3/2 quasiparticles, the possibility of high-spin Cooper pairing (i.e. beyond triplet) with non-trivial topology analogous to that predicted for the normal state electronic structure provides a unique and rich opportunity to realize both predicted and new exotic excitations in topological materials.