TY - JOUR

T1 - Exotic Spin Structures in Transition-Metal Monosilicides and Monogermanides

AU - Altynbaev, E. V.

AU - Chubova, N. M.

AU - Grigoriev, S. V.

N1 - Publisher Copyright: © 2022, Pleiades Publishing, Inc.

PY - 2022/2/1

Y1 - 2022/2/1

N2 - Abstract: Monosilicides and monohermanides of transition metals (e.g., MnSi) are characterized by a noncentrosymmetric structure of the B20 type, which leads to the occurrence of the Dzyaloshinski–Moriya (DM) interaction and, as a consequence, helicoidal magnetic ordering. The sign of the DM interaction determines the direction (clockwise or anticlockwise) of magnetic-helicoid twist. It is found that the type of atoms (e.g., Mn and Fe) present in a compound corresponds unambiguously to the sign of DM interaction in both silicides and germanides of transition metals. In turn, the replacement of Mn with Fe atoms in Mn1-xFexGe (and some other) solid solutions results in a flip of the magnetic system chirality. These compounds demonstrates also a complex nature of the first-order temperature phase transition (close to the second-order one), complicated by a multicomponent order parameter and accompanied by a wide range of critical helical fluctuations. The magnetic field–temperature (H–T) phase diagram demonstrates occurrence of a new phase with a skyrmion lattice structure, or A-phase, in a narrow range of fields near the phase-transition point. Application of pressure or replacement of Mn with Fe or Co atoms leads to disappearance of long-range magnetic order and occurrence of a quantum phase transition. This review contains the experimental results obtained using small-angle neutron scattering (SANS) and characterizing the magnetic properties and phase diagrams of helicoidal magnets.

AB - Abstract: Monosilicides and monohermanides of transition metals (e.g., MnSi) are characterized by a noncentrosymmetric structure of the B20 type, which leads to the occurrence of the Dzyaloshinski–Moriya (DM) interaction and, as a consequence, helicoidal magnetic ordering. The sign of the DM interaction determines the direction (clockwise or anticlockwise) of magnetic-helicoid twist. It is found that the type of atoms (e.g., Mn and Fe) present in a compound corresponds unambiguously to the sign of DM interaction in both silicides and germanides of transition metals. In turn, the replacement of Mn with Fe atoms in Mn1-xFexGe (and some other) solid solutions results in a flip of the magnetic system chirality. These compounds demonstrates also a complex nature of the first-order temperature phase transition (close to the second-order one), complicated by a multicomponent order parameter and accompanied by a wide range of critical helical fluctuations. The magnetic field–temperature (H–T) phase diagram demonstrates occurrence of a new phase with a skyrmion lattice structure, or A-phase, in a narrow range of fields near the phase-transition point. Application of pressure or replacement of Mn with Fe or Co atoms leads to disappearance of long-range magnetic order and occurrence of a quantum phase transition. This review contains the experimental results obtained using small-angle neutron scattering (SANS) and characterizing the magnetic properties and phase diagrams of helicoidal magnets.

UR - http://www.scopus.com/inward/record.url?scp=85124943835&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/ec3046b0-588f-3548-819f-331f7079f801/

U2 - 10.1134/s1063774522010023

DO - 10.1134/s1063774522010023

M3 - Review article

AN - SCOPUS:85124943835

VL - 67

SP - 118

EP - 136

JO - Crystallography Reports

JF - Crystallography Reports

SN - 1063-7745

IS - 1

ER -