The outrageous properties of the rare – earth nitrides
Semiconductor spin-orbit ferromagnetism
Strongly correlated electron gas
Topological insulator? Superconductor?
Professor Joe Trodhal
Victoria University of Wellington, New Zealand
10th June 2019
Lecture theatre C44 Biomedical Science building
In 2005 we set up to investigate the mononitrides of the rare earths, LN, L a lanthanide element, an endeavour in which the collaboration of the Valbonne laboratory (CNRS/CRHEA) has been enormously valuable. The LN form the only series of intrinsic (i.e. dopable) ferromagnetic semiconductors, with obvious potential exploitation in spin-orbitronics. We started investigating these compounds a decade ago, motivated by a prediction of half metals among their number, only to discover their semiconducting nature. In the past few years we began work on LN/L’N heterostructures and tunnelling structures. Along the way there have been many surprises, most recently that one of the series, near-zero-magnetisation ferromagnetic SmN, is superconducting below 4 K. My talk will discuss the growth and properties, and carry on to the most outrageous nano-structured and low dimensional strongly correlated and predicted topological states.
 F. Natali et al, Prog. Materials Science 58, 1316 (2013).  C. M. Aerts et al., Phys. Rev. B 69, 045115 2004.  H. Warring et al, Phys. Rev. Appl. 6, 044002 (2016).  E.-M. Anton et al, Phys. Rev. B 94, 024106 (2016).