⁸Li βNMR studies of Epitaxial Thin Films of the 3D topological Dirac semimetal Sr₃SnO

Abstract The inverse perovskite Sr 3 SnO is a 3D cubic Dirac semimetal with very small energy gap[1]. Its unusual electronic structure confers variety of novel properties, such as chiral topological surface states, and strong itinerant electron orbital magnetism. Remarkably, when doped it also becomes superconducting[2]. In the lowest carrier density samples, Fermi level lies close to points, magnetism maximal. Here we report results ion-implanted 8 Li + β NMR in Au-capped epitaxial thin films function content. addition, stop Au overlayer seek proximal evidence state. high magnetic field (6.55 T), find remarkably little contrast spin-lattice relaxation (SLR) between low overlayer. layer, 1/ T 1 ∼ 0.14 s -1 , slightly faster than at 300 K, while overlayer, there but systematic enhancement compared control film Au. resonance layer broad long tail towards negative shift without resolved quadrupolar splitting.