Magnetocapacitance

About: Magnetocapacitance is a research topic. Over the lifetime, 497 publications have been published within this topic receiving 23846 citations.

Large magnetodielectric response of PST/LSMO/LCMO film over a wide temperature range

Abstract: Pb06Sr04TiO3/La07Sr03MnO3/La07Ca03MnO3 (PST/LSMO/LCMO) film is grown on Si substrate by chemical solution deposition method The film crystallizes perfectly into perovskite phases with a random crystalline orientation The La07Sr03MnO3/La07Ca03MnO3/Si layer exhibits low resistivity and obvious negative magnetoresistivity (MR); the PST/LSMO/LCMO film shows notable magnetocapacitance (MC) above 350 K, from 1029% to 295% Near room temperature, there is no distinguished magnetoelectric coupling; the MC is 343% @ 250 K, 295% @ 300 K and 328% @ 350 K respectively The mechanism can be explained in light of the Maxwell–Wagner (MW) model and the enhanced MR origin from the successive mixed manganite phases and spin dependent tunneling across the junctions of PST/LSMO/LCMO This work provides a new approach for designing and developing novel composites with promising MC

Coupled Order Parameters in Magneto-Ferrolectrics

Abstract: Recent observations of the simultaneous appearance of non-collinear magnetic order and spontaneous polarization in a special class of multiferroics have revived the interest in the magnetoelectric effect. These phenomena have so far been observed in TbMnO3 [1–4], DyMnO3 [2, 3] and Tb1–xDyxMnO3 [5] with an orthorhombically distorted perovskite structure by rotation of the MnO6 octahedra, and in Ni3V2O8 [6], in which the Ni2+ ions form a Kagome staircase. The strong coupling between magnetic order and ferroelectricity gives rise to giant magnetoelectric and magnetocapacitance effects. I will concentrate in this note on the case of TbMnO3. In this compound, there first appears at T = 41 K a collinear modulated sin-wave structure of Mn3+ spins,

Local electron density near the 2DES boundary formed by side-gate voltage in the quantum Hall regime

Abstract: Spatial distribution of the edge states in the quantum Hall (QH) effect has been investigated by the magnetocapacitance technique. The relation between the edge states and electron distribution at the sample boundary in the QH regime has been discussed. We have measured the capacitance between a two dimensional electron system and each thin wire gate at 0.4 K with applying negative voltage to the side gate and obtained the local density profile near the sample boundary. The spatial profile of confinement potential is much gentle when strong negative side gate bias is applied and the electron density at the interior region (more than 10 μm far from the side gate) is affected by side gate voltage.

Magnetocapacitance in CdCr 1.8 In 0.2 S 4 Single Crystal Annealed in Cadmium Vapor

Abstract: CdCr2S4 single crystal was reported by Hemberger et al. to be multiferroic with the evidences of relaxor ferroelectricity and colossal magnetocapacitance (CMC), but whether these effects are intrinsic is under debate. Recently, we reported a one-to-one correlation between CMC and colossal magnetoresistance (CMR) in CdCr2S4 polycrystalline samples, and argued that CMC could be explained by the superposition of the CMR and the Maxwell–Wagner effects. In this paper, we further examined the magnetic, dielectric, and electric transport properties of CdCr2S4 and CdCr1.8In0.2S4 single crystals before and after annealing in cadmium vapor. The CdCr2S4 single crystal sample has no relaxor ferroelectricity and CMC, and in contrast to the CdCr2S4 single crystal reported by Hemberger et al. , only the annealed CdCr1.8In0.2S4 displays CMC, but still does not exhibit the relaxor behavior. At the same time, it also shows CMR. All these results are in accordance with the results of our polycrystalline samples, and further confirm the resistive origin of the CMC in the CdCr2S4 system.

Change of the magnetocapacitance ratio in ferromagnetic materials

Abstract: The magnetostriction effect, the change in the mechanical properties of a magnetic material in an external magnetic field, has been studied for possible technological applications such as actuators. We present the fabrication of a multilayered magnetocapacitor containing magnetic layers of Ni0.98Co0.02Fe2O4 (NCFO) and compare it with our prior magnetocapacitor in which CoFe2O4 (CFO) and CoNiFe (CNF) were used as the magnetic layers. In particular, we measured the surface/interface microstructures and the change in the lattice constant of the BaTiO3 (BTO) film in NCFO/BTO/NCFO, CFO/BTO/CFO, and CNF/BTO/CNF multilayered thin films. Our study suggests that there is a correlation exists between the magnetocapacitance and the lattice constant of BTO, which varies with the type of ferromagnetic (FM) material embedded in the magnetic layer.