Correlated oxide Dirac semimetal in the extreme quantum limit

Abstract

Quantum materials (QMs) with strong correlation and nontrivial topology are indispensable to next-generation information and computing technologies. Exploitation of topological band structure is an ideal starting point to realize correlated topological QMs. Here, we report that strain-induced symmetry modification in correlated oxide SrNbO 3 thin films creates an emerging topological band structure. Dirac electrons in strained SrNbO 3 films reveal ultrahigh mobility ( max ≈ 100,000 cm 2 /Vs), exceptionally small effective mass (m* ~ 0.04m e ), and nonzero Berry phase. Strained SrNbO 3 films reach the extreme quantum limit, exhibiting a sign of fractional occupation of Landau levels and giant mass enhancement. Our results suggest that symmetry-modified SrNbO 3 is a rare example of correlated oxide Dirac semimetals, in which strong correlation of Dirac electrons leads to the realization of a novel correlated topological QM.

Preparation of large Cu3Sn single crystal by Czochralski method

“…4b, indicating that the unusual MR of Cu 3 Sn is related to its low-energy electronic structure. Such behavior is usually an indication of non-trivial low-energy electronic structures, for example perfectly compensated electron/hole Fermi surface [14,15], strong inhomogeneityinduced charge/mobility fluctuation [16], and topological Dirac/Weyl semimetals [17][18][19]. Among the possibilities, the quasi-linear MR of Cu 3 Sn is likely due to its topological electronic band structure.…”

Towards actinide heterostructure synthesis and science

“…The ability to synthesize epitaxial thin films and heterostructures from a wide range of quantum materials, including topological insulators and strongly correlated oxides, is now a rapidly expanding research area 11 . The exploration of actinide heterostructures would represent a novel direction for these efforts.…”

Electric field control of anomalous Hall effect in CaIrO$_3$/CaMnO$_3$ heterostructure

“…Our work provides important insight into the origin and manipulation of AHE in the oxide heterointerfaces with Dirac-like band dispersion. Also recently, emergence of Dirac electrons has been reported in strained SrNbO 3 thin films [25,26],…”