Dielectric properties of single crystal spinels in the series FeV2O4, MnV2O

Ade Kismarahardja

¹

,

J. S. Brooks

²

,

H. D. Zhou

³

et al.

Abstract

We report a comparative investigation of the magnetostrictive and magnetoconductivity effects in the low temperature ferrimagnetic phases of the spinel vanadate structure AV 2 O 4 where A = Fe, Mn, and Co. In temperature and magnetic field exhibit distinctive physical properties in each case. These include the magneto-caloric signatures of magnetization reversal (Fe and Co), separable isotropic and anisotropic magnetostrictive effects (Mn), glass-like dynamics (Co), and evidence in the fielddependent dielectric response for the alteration of the ferrimagnetic spin structure with increasing 2 magnetic field (Fe). These findings can guide future dielectric-and magnetoconductance-based spinel studies with a focus on the low temperature and high magnetic field properties of canted ferrimagnetic spin configurations and orbital-lattice ordering effects. 75.25.+z, 75.50.Gg, 75.80.+q, 71.70 PACS numbers

Structural and Magnetic Properties in Spinel Oxide Fe1−xMnxV2O4

“…Whereas, ferrimagnetic (FM) transition with the Fe 2+ and V 3+ moments anti-aligned at T N1 = 110 K and non-collinear ferrimagnetic (NFM) transitions at T N2 = 60 K was reported [5]. Further, spin-glass behavior was observed at 85 K [7], and magnetic field dependent ferroelectricity was found [8][9][10]12]. Very recently, orbital states of Fe 2+ and V 3+ ions were studied using single crystal X-ray diffraction experiments and first-principles electronic structure calculation [6,11], and it was reported that the cooperative Jahn-Teller (JT) effects and relativistic spin-orbit (SO) coupling play an important role in the phase transitions.…”

“…Recently, vanadium spinels AV 2 O 4 , where the divalent A 2+ (A = Mn, Fe, Co, Zn, Mg, and Cd) and the trivalent V 3+ ions occupy the tetrahedral (A-site) and the octahedral (B-site) sites in a normal spinel structure, respectively, have been studied intensively because of the variety of interesting phenomena related with orbital degrees of freedom because the V 3+ ions have 3d 2 configurations in the triply degenerate t 2g level [1][2][3][4][5][6][7][8][9][10][11][12][13][14].…”

Structural and magnetic anisotropy in the epitaxial FeV2O4 (110) spinel thin films

“…14 16 So far numerous investigations about FVO bulk have been performed. [2][3][4][5][6][7][8]17 However, studies on the FVO thin films have just started. Previously, we prepared FVO (001) thin films on (001)-orientated STO, LAO, and MAO substrates, 18 and biaxial strain was observed in the film plane.…”

“…FVO bulk exhibits a rich phase diagram and various novel phenomena such as spin frustration, 1 multiferroicity, 2-4 orbital ordering, [5][6][7] and magnetostriction. 8,9 With decreasing temperature, three successive structural phase transitions in stoichiometric FVO were reported 9 : from cubic to high temperature tetragonal (c < a) at T S =140 K, from high temperature tetragonal (c < a) to orthorhombic at T N1 =110 K, and from orthorhombic to low temperature tetragonal (c > a) at T N2 =70 K. The latter two are accompanied by two magnetic phase transitions, indicating the strong coupling between the magnetism and lattice.…”

Variety of elastic anomalies in an orbital-active nearly itinerant cobalt vanadate spinel

“…For AV 2 O 4 (A = Zn, Mg, Cd, Mn, and Fe), the structural phase transition is considered to arise from a longrange ordering of the V t 2g orbitals, where the lowering of the lattice symmetry should result in the release of frustration (magnetic ordering). The orbital order to explain the structural and magnetic orders for AV 2 O 4 is still under debate both theoretically [ [25][26][27][28][29][30][31] and experimentally [ 4,7,12,15 ]; it is considered to be driven by the competition among Jahn-Teller coupling, Kugel- ) is a unique vanadate spinel with its highest electrical conductivity among the insulating or semiconducting AV 2 O 4 , which is considered to arise from the nearly-itinerant character of the V 3d electrons [ [33][34][35][36][37][38][39]. CoV 2 O 4 exhibits a ferrimagnetic order below T C ∼ 150 K, which is similar to AV 2 O 4 with magnetic A = Mn (T C = 57 K) and Fe (T C = 110 K).…”