title: Observation of antiferromagnetic order collapse in the pressurized insulator LaMnPO.
abstract: The emergence of superconductivity in the iron pnictide or cuprate high temperature superconductors usually accompanies the suppression of a long-ranged antiferromagnetic (AFM) order state in a corresponding parent compound by doping or pressurizing. A great deal of effort by doping has been made to find superconductivity in Mn-based compounds, which are thought to bridge the gap between the two families of high temperature superconductors, but the AFM order was not successfully suppressed. Here we report the first observations of the pressure-induced elimination of long-ranged AFM order at ~ 34 GPa and a crossover from an AFM insulating to an AFM metallic state at ~ 20 GPa in LaMnPO single crystals that are iso-structural to the LaFeAsO superconductor by in-situ high pressure resistance and ac susceptibility measurements. These findings are of importance to explore potential superconductivity in Mn-based compounds and to shed new light on the underlying mechanism of high temperature superconductivity.
authors.affiliation: Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Guo
authors.forename: J W
authors.initials: JW
authors.lastname: Simonson
authors.forename: Liling
authors.initials: L
authors.lastname: Sun
authors.forename: Qi
authors.initials: Q
authors.lastname: Wu
authors.forename: Peiwen
authors.initials: P
authors.lastname: Gao
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.forename: Dachun
authors.initials: D
authors.lastname: Gu
authors.forename: Gabriel
authors.initials: G
authors.lastname: Kotliar
authors.forename: Meigan
authors.initials: M
authors.lastname: Aronson
authors.forename: Zhongxian
authors.initials: Z
authors.lastname: Zhao
mesh_terms: D004553:Electric Conductivity; D060526:Magnetic Fields; D008422:Materials Testing; D008670:Metals / Q000737:chemistry*; D011312:Pressure
chemical_list: D008670:Metals