title: Spiral magnetic order and pressure-induced superconductivity in transition metal compounds.
abstract: Magnetic and superconducting ground states can compete, cooperate and coexist. MnP provides a compelling and potentially generalizable example of a material where superconductivity and magnetism may be intertwined. Using a synchrotron-based non-resonant X-ray magnetic diffraction technique, we reveal a spiral spin order in MnP and trace its pressure evolution towards superconducting order via measurements in a diamond anvil cell. Judging from the magnetostriction, ordered moments vanish at the quantum phase transition as pressure increases the electron kinetic energy. Spins remain local in the disordered phase, and the promotion of superconductivity is likely to emerge from an enhanced coupling to residual spiral spin fluctuations and their concomitant suppression of phonon-mediated superconductivity. As the pitch of the spiral order varies across the 3d transition metal compounds in the MnP family, the magnetic ground state switches between antiferromagnet and ferromagnet, providing an additional tuning parameter in probing spin-fluctuation-induced superconductivity.
authors.affiliation: Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: Yishu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, California 91125, USA.|The Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: Yejun
authors.identifier: 0000-0003-3667-056X
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: J-G
authors.initials: JG
authors.lastname: Cheng
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: W
authors.initials: W
authors.lastname: Wu
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing 100190, China.
authors.forename: J L
authors.initials: JL
authors.lastname: Luo
authors.affiliation: Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: T F
authors.initials: TF
authors.lastname: Rosenbaum