Dielectric properties of (Bi0.9La0.1)2NiMnO

Eric Langenberg

¹

,

Ignasi Fina

²

,

J. Ventura

³

et al.

Abstract

We have used temperature-dependent impedance spectroscopy to study the dielectric response of thin films of ferromagnetic and ferroelectric (Bi 0.9 La 0.1 ) 2 NiMnO 6 oxide. This technique has allowed us to disentangle its intrinsic dielectric response and extract the dielectric permittivity of ∼220, which is in close agreement with bulk values but significantly smaller than early reported values for similar thin films. The permittivity is found to be temperature independent in the vicinity of the ferromagnetic transition temperature and independent of magnetic field. We have shown that the measured magnetocapacitance arises from the magnetoresistance of the films, thus indicating a negligible magnetoelectric coupling in these double perovskites, probably due to the different energy scales and mechanisms of ferroelectric and magnetic order.

Optical probe of ferroelectric order in bulk and thin-film perovskite titanates

“…Direct capacitance or impedance spectroscopy measurements of the FE order on such thin films are often complicated and hindered by parasitic charges forming at interfaces and electrodes that can obscure the FE contribution. 6,7 Dedicated techniques such as piezoresponse force microscopy, 8 synchrotron x-ray diffraction, 9,10 or ultraviolet Raman spectroscopy 11 have therefore been used to detect the FE order in very thin films. In the following, we show that standard optical spectroscopy measurements of the temperature (T ) dependence of the direct band gap E g can be used as an alternative and very effective tool to identify such a FE transition.…”

Dielectric characterization of multiferroic magnetoelectric double-perovskite Y(Ni0.5Mn0.5)O3 thin films

“…In Figure 3 In the low frequency contribution the extracted permittivity is as high as ≈500 for both samples, which is extremely high and differ in large amount from the already reported values denoting its extrinsic origin 37 . Therefore, it has been ascribed to interfacial extrinsic effects, as observed in other detailed studies in similar materials 51,52 . The high frequency contribution has been ascribed to the intrinsic dielectric behaviour of the film In Figure 5(c), we show the normalized M(H)/Mo loops recorded at 5K, confirming the ferromagnetic nature of the films, which results from the ferromagnetic coupling between the adjacent nikel and manganeses ions.…”

“…We will investigate two set of films in order to access information along different directions: YNMO (001) Impedance data have been analysed in order to extract the intrinsic dielectric permittivity of the film, as further described in this article, following analyses described elsewhere 51,52 .…”

Cationic ordering and Dielectric Relaxation in a New Series of Double Perovskite BaNdCoXO6 (X = Nb, Sb and Ta)

“…This special class of magnetic materials, especially ferrite, perovskite and double perovskite, has shown many unusual physicochemical properties and wide range of technological applications [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Each one of the above mentioned magnetic oxides, i.e., ferrite, perovskite and double perovskite, has their own domain of interests.…”