Tailoring the magnetic and magnetoelectric properties of rare earth orthoferrites for room temperature applications

RSC Advances ◽  
2016 ◽  
Vol 6 (76) ◽  
pp. 72295-72299 ◽  
Author(s):  
N. Ramu ◽  
R. Muralidharan ◽  
K. Meera ◽  
Y. H. Jeong
Keyword(s):  
Dielectric Constant ◽  
Rare Earth ◽  
Transition Temperature ◽  
Dielectric Loss ◽  
Room Temperature ◽  
Magnetic Transition ◽  
Magnetic Transition Temperature ◽  
Magnetoelectric Properties ◽  
Negative Magnetization ◽  
Temperature Applications

The M(T) curve shows negative magnetization value for samples containing Er ions. The dielectric constant value does not show any anomaly around the magnetic transition temperature. The temperature at which maximum MDE effect observed corresponds to dielectric loss maxima.

Effect of Gd Substitution on the Dielectric Properties and Magnetoelectric Effect of BiFeO3

2010 ◽  
Vol 150-151 ◽  
pp. 1470-1475
Author(s):  
Gui Lin Song ◽  
Tian Xing Wang ◽  
Cun Jun Xia ◽  
Chao Li ◽  
Fang Gao Chang
Keyword(s):  
Dielectric Constant ◽  
Rare Earth ◽  
Dielectric Loss ◽  
Room Temperature ◽  
Magnetoelectric Effect ◽  
Solid State Reaction Method ◽  
Impurity Phase ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Dielectric Relaxation Process

Multiferroic Bi1-xGdxFeO3(x=0, 0.05, 0.1, 0.15, 0.2) ceramics were prepared by conventional solid state reaction method. For all the samples prepared, they exhibit magnetoelectric effect at room temperature, and the dielectric constant and dielectric loss decrease with increasing frequency in the range from 10000Hz to 1 MHz from a typical orientational dielectric relaxation process. It has been found that both dielectric constant and dielectric loss are strongly dependent on the Gd3+ content. And substitution of Bi with rare earth Gd helps to eliminate the impurity phase in BiFeO3 ceramics.,

Dielectric, Piezoelectric and Magnetic Properties of Ferroelectromagnet Pb(Fe1/3Nb2/3)O3(PFN) Ceramics

2003 ◽  
Vol 17 (18n20) ◽  
pp. 3732-3737 ◽  
Author(s):  
Jin. T. Wang ◽  
Marx K. Mbonye ◽  
Cheng Zhang
Keyword(s):  
Crystal Structure ◽  
Dielectric Constant ◽  
Magnetic Properties ◽  
Transition Temperature ◽  
Dielectric Loss ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Dielectric Constant ◽  
Piezoelectric Strain

Ferroelecromagnet Pb ( Fe 1/3 Nb 2/3) O 3 has been synthesized and its crystal structure and dielectric, electrostrictive and magnetic properties have been investigated. The structure of PFN ceramics examined by X-ray diffraction was found perovskite-like. The dielectric constant and dielectric loss as a function of temperature at different frequencies was measured. A para-ferroelectric transition at a temperature of 403 K was found and the maximum dielectric constant at a frequency of 500 Hz at the transition temperature is as high as 9050. The piezoelectric strain at room temperature was examined. The magnetization measurements as a function of temperature in the temperature region from room temperature to 648 K with different applied magnetic fields revealed that the compound is antiferromagnetic.

Silk Polymer Coating with Low Dielectric Constant and High Thermal Stability for Ulsi Interlayer Dielectric

1997 ◽  
Vol 476 ◽  
Author(s):  
P. H. Townsend ◽  
S. J. Martin ◽  
J. Godschalx ◽  
D. R. Romer ◽  
D. W. Smith ◽  
...  
Keyword(s):  
Thin Film ◽  
Dielectric Constant ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Integrated Circuits ◽  
Room Temperature ◽  
Polymer Network ◽  
Flow Characteristics ◽  
Interlayer Dielectric

AbstractA novel polymer has been developed for use as a thin film dielectric in the interconnect structure of high density integrated circuits. The coating is applied to the substrate as an oligomeric solution, SiLK*, using conventional spin coating equipment and produces highly uniform films after curing at 400 °C to 450 °C. The oligomeric solution, with a viscosity of ca. 30 cPs, is readily handled on standard thin film coating equipment. Polymerization does not require a catalyst. There is no water evolved during the polymerization. The resulting polymer network is an aromatic hydrocarbon with an isotropie structure and contains no fluorine.The properties of the cured films are designed to permit integration with current ILD processes. In particular, the rate of weight-loss during isothermal exposures at 450 °C is ca. 0.7 wt.%/hour. The dielectric constant of cured SiLK has been measured at 2.65. The refractive index in both the in-plane and out-of-plane directions is 1.63. The flow characteristics of SiLK lead to broad topographic planarization and permit the filling of gaps at least as narrow as 0.1 μm. The glass transition temperature for the fully cured film is greater than 490 °C. The coefficient of thermal expansivity is 66 ppm/°C below the glass transition temperature. The stress in fully cured films on Si wafers is ca. 60 MPa at room temperature. The fracture toughness measured on thin films is 0.62 MPa m ½. Thin coatings absorb less than 0.25 wt.% water when exposed to 80% relative humidity at room temperature.

Effect of A-site cation substitution on magnetic transition temperature of (LaCa) MnO3

1999 ◽  
Vol 42 (7) ◽  
pp. 758-762
Author(s):  
Kebin Li ◽  
Shouguo Wang ◽  
Rongsheng Cheng ◽  
Xijun Li ◽  
Denglu Hou ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Magnetic Transition ◽  
Cation Substitution ◽  
Magnetic Transition Temperature ◽  
A Site

Direct Synthesis of Chromium Perovskite Oxyhydride with a High Magnetic-Transition Temperature

2014 ◽  
Vol 126 (39) ◽  
pp. 10545-10548 ◽  
Author(s):  
Cédric Tassel ◽  
Yoshihiro Goto ◽  
Yoshinori Kuno ◽  
James Hester ◽  
Mark Green ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Magnetic Transition ◽  
Direct Synthesis ◽  
Magnetic Transition Temperature

Magnetic Phase Transitions and Magnetocaloric Effect in R2Fe17 (R = Y, Tb, Er)

2015 ◽  
Vol 233-234 ◽  
pp. 204-207 ◽  
Author(s):  
S.A. Nikitin ◽  
I.A. Ovchenkova ◽  
Georgiy A. Tskhadadze ◽  
Konstantin P. Skokov
Keyword(s):  
Transition Temperature ◽  
Magnetocaloric Effect ◽  
Magnetic Phase ◽  
Magnetic Transition ◽  
Exchange Interactions ◽  
Thermodynamic Theory ◽  
Magnetic Phase Transitions ◽  
Magnetic Transition Temperature ◽  
Local Fluctuations ◽  
Direct Measurements

The direct measurements of the magnetocaloric effect (MCE) and the magnetization for R2Fe17 (R = Y, Tb, Dy) compounds are reported. The maximal values of the MCE for different R2Fe17 compounds are almost the same at the Curie temperature and are equal to 0.8 – 0.85 K at ΛH = 13.5 kOe. The field dependencies of the magnetization and MCE and the dependence of MCE via magnetization deviates from the classical regularities and describes by the thermodynamic theory attracting the higher terms. Obviously the occurrence of the mixed exchange interactions in these compounds leads to the requirement of consideration both thermal and local fluctuations of the exchange integrals near the magnetic transition temperature.

scholarly journals Dielectric properties and conductivity of PVdF-co-HFP/LiClO4 polymer electrolytes

2018 ◽  
Vol 96 (7) ◽  
pp. 786-791 ◽  
Author(s):  
Kemal Ulutaş ◽  
Ugur Yahsi ◽  
Hüseyin Deligöz ◽  
Cumali Tav ◽  
Serpil Yılmaztürk ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Polymer Electrolytes ◽  
Room Temperature ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Maximum Conductivity

In this study, it was aimed to prepare a series of PVdF-co-HFP based electrolytes with different LiClO4 loadings and to investigate their chemical and electrical properties in detail. For this purpose, PVdF-co-HFP based electrolytes with different LiClO4 loadings (1–20 weight %) were prepared using solution casting method. X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric (TGA) –differential thermal and dielectric spectroscopy analysis of PVdF-co-HFP/LiClO4 were performed to characterize their structural, thermal, and dielectric properties, respectively. XRD results showed that the diffraction peaks of PVdF-co-HFP/LiClO4 electrolytes broadened and decreased with LiClO4. TGA patterns exhibited that PVdF-co-HFP/LiClO4 electrolytes with 20 wt % of LiClO4 had the lowest thermal stability and it degraded above 473 K, which is highly applicable for solid polymer electrolytes. Dielectric constant, dielectric loss, and conductivities were calculated by measuring capacitance and dielectric loss factor of PVdF-co-HFP/LiClO4 in the range from 10 mHz to 20 MHz frequencies at room temperature. In consequence, conductivities of PVdF-co-HFP/LiClO4 increased significantly with frequency for low loading of LiClO4 while they only slightly changed with higher LiClO4 addition. On the other hand, dielectric constant values of PVdF-co-HFP/LiClO4 films decreased with frequency whereas they rose with LiClO4 addition. The dielectric studies showed an increase in dielectric constant and dielectric loss with decreasing frequency. This result was attributed to high contribution of charge accumulation at the electrode–electrolyte interface. The electrolyte showed the maximum conductivity of 8 × 10−2 S/cm at room temperature.

Enhanced magnetoelectric coupling and dielectric constant in flexible ternary composite electrospun fibers of PVDF-HFP loaded with nanoclay and NiFe2O4 nanoparticles

2020 ◽  
Vol 44 (26) ◽  
pp. 11356-11364
Author(s):  
Sobi K. Chacko ◽  
M. T. Rahul ◽  
B. Raneesh ◽  
Nandakumar Kalarikkal
Keyword(s):  
Dielectric Constant ◽  
Room Temperature ◽  
Composite Fiber ◽  
Magnetoelectric Coupling ◽  
Electrospun Fibers ◽  
Fiber Mats ◽  
Ternary Composite ◽  
Magnetoelectric Properties ◽  
Nife2o4 Nanoparticles

Magnetoelectric flexible composite fiber mats with superior room temperature magnetoelectric properties.

Sign in / Sign up

Export Citation Format

Share Document