Magnetoelectric effects in an organo-metallic quantum magnet

Abstract

We observe a bilinear magnetic field-induced electric polarization of 50 $\mu C/m^2$ in single crystals of NiCl${}_2$-4SC(NH${}_2$)${}_2$ (DTN). DTN forms a tetragonal structure that breaks inversion symmetry, with the highly polar thiourea molecules all tilted in the same direction along the c-axis. Application of a magnetic field between 2 and 12 T induces canted antiferromagnetism of the Ni spins and the resulting magnetization closely tracks the electric polarization. We speculate that the Ni magnetic forces acting on the soft organic lattice can create significant distortions and modify the angles of the thiourea molecules, thereby creating a magnetoelectric effect. This is an example of how magnetoelectric effects can be constructed in organo-metallic single crystals by combining magnetic ions with electrically polar organic elements.

3 pages, 3 figures

References in corpus (8)

• Spin current and magneto-electric effect in non-collinear magnets
• Stochastic series expansion method with operator-loop update
• Magnetically driven ferroelectric order in Ni${}_3$V${}_2$O${}_8$
• Bose-Einstein Condensation of S = 1 Ni spin degrees of freedom in NiCl2-4SC(NH2)2
• Direct transition from a disordered to a multiferroic phase on a triangular lattice
• Magnetic Excitations in the Spin-1 Anisotropic Heisenberg Antiferromagnetic Chain System NiCl${}_2$-4SC(NH${}_2$)${}_2$
• A direct measurement of the Bose-Einstein Condensation universality class in NiCl${}_2$-4SC(NH${}_2$)${}_2$ at ultra-low temperatures
• Spin Dynamics of $NiC{l}_2-4SC(N{H}_2{)}_2$ in the Field-Induced Ordered Phase

Cited by in corpus (6)

• Phase Diagram and Magnetic Excitations of Anisotropic Spin-One Magnets
• Electric polarization observed in single crystals of multiferroic Lu2MnCoO6
• High magnetic field evolution of ferroelectricity in CuCrO2
• Partially disordered antiferromagnetism and multiferroic behavior in a frustrated Ising system, CoCl${}_2$-2SC(NH${}_2$)${}_2$
• Field-induced spin level crossings within a quasi-XY antiferromagnetic state in Ba${}_2$FeSi${}_2$O${}_7$
• Dzyaloshinskii-Moriya Interaction-Induced Magnetoelectric Coupling in a tetrahedral Molecular Spin-Frustrated System