Changes in magnetic properties of MnSe by Sulfur doping
Chun-Hao Huang1,2*, Chin-Wei Wang3, Ming-Jye Wang4, Maw-Kuen Wu2
1Department of Physics, National Taiwan University, Taipei, Taiwan
2Institute of Physics, Academia Sinica, Taipei, Taiwan
3Neutron group, National Synchrotron Radiation Research Center, Hsinchu, Taiwan
4Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan
* Presenter:Chun-Hao Huang,
The observation of superconductivity in MnP under pressure motivated us to investigate whether MnSe(S) system [1] will behaviour similarly. In this report, we studied the chemical substitution effects on MnSe by sulphur-doping. Our detailed structural studies using synchrotron X-ray and neutron diffractions confirm the coexistence of cubic and hexagonal phase in cooling, which also shows strong hysteresis suggestion the first-order nature of the phase transition. [2], but also patch the investigation under warming process by synchrotron source. Based on the temperature dependent magnetic susceptibility results we verify the complex magnetism in MnSe is strongly modified by the substitution of sulfur element. However, sulfur substitution does exhibit a more complicated magnetic structure at low temperature, but does not induce superconductivity. An interesting observation is the strong magnetic susceptibility in MnS below 16 K without any signature of magnetic structure change in neutron powder diffraction patterns. Our specific heat measurements on MnS show extra contribution T3/2 beyond phonon T3, which suggest the possible contribution from disorder ferromagnetism.

Keywords: MnSe, MnS, magnetic susceptibility, Crystal and magnetic structure