Successive incommensurate spin orderings and excitations in multiferroic SrMnGe2O6

Abstract

Anisotropic multiferroic properties of SrMnGe2O6 pyroxene single crystals were systematically investigated by means of magnetization, heat capacity, pyroelectric current measurement and elastic and inelastic neutron scattering experiments. Single crystal neutron diffraction allows us to unambiguously reveal the presence of two incommensurate magnetic orderings: a non-polar amplitude-modulated collinear sinusoidal magnetic structure emerges at TN1=4.36(2)K followed by a polar elliptical cycloidal spin structure below TN2=4.05(2)K. Pyroelectric current measurements on single crystal confirm the appearance of a spontaneous polarization within the (ac) plane below TN2 associated with the latter magnetic symmetry through extended Dzyaloshinsky-Moriya mechanism. The magnetic phase diagram was calculated considering the three isotropic exchange couplings relevant in this system. The magnetic excitations spectra of SrMnGe2O6 measured by inelastic neutron scattering were successfully modeled using a set of exchange interactions consistent with this phase diagram.

References in corpus (15)

• Spin current and magneto-electric effect in non-collinear magnets
• Ferroelectricity in spiral magnets
• Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites
• Magnetic inversion symmetry breaking and ferroelectricity in TbMnO3
• Magnetoelectric MnPS3 thiophosphate as a new candidate for ferrotoroidicity
• Canted-spin-caused electric dipoles: a local symmetry theory
• Pyroxenes: A new class of multiferroics
• Electronic structure and magnetic properties of pyroxenes (Li,Na)TM(Si,Ge)2O6: novel low-dimensional magnets with 90 bonds
• Magnetic superspace groups and symmetry constraints in incommensurate magnetic phases
• Multiferroicity in the generic easy-plane triangular lattice antiferromagnet RbFe(MoO4)2
• Magnetic pyroxenes LiCrGe2O6 and LiCrSi2O6: dimensionality crossover in a non-frustrated S=3/2 Heisenberg model
• Muon-spin relaxation and heat capacity measurements on the magnetoelectric and multiferroic pyroxenes LiFeSi2O6 and NaFeSi2O6
• Anisotropy study of multiferroicity in the pyroxene NaFeGe${}_2$O${}_6$
• Unravelling the complex magnetic structure of multiferroic pyroxene NaFeGe2O6: A combined experimental and theoretical study
• Mechanism of ferromagnetic ordering of the Mn chains in CaMnGe${}_2$O${}_6$ clinopyroxene

Cited by in corpus (4)

• Chiral Order and Multiferroic Domain Relaxation in NaFeGe${}_2$O${}_6$
• Incommensurate Spiral Spin Order in CaMn${}_2$Bi${}_2$ observed via High Pressure Neutron Diffraction
• Direct evidence for intermediate multiferroic phase in LiCuFe2(VO4)3
• Spin dynamics in natural multiferroic pyroxene NaFeSi${}_2$O${}_6$