Correlation of cation deficiency and nanostructure to decreased magnetism in a ferroelectric BiMnO3 film

2019 ◽  
Vol 126 (8) ◽  
pp. 085303
Author(s):  
Daniel M. Pajerowski ◽  
Lisa A. Krayer ◽  
Hyoungjeen Jeen ◽  
Julie A. Borchers ◽  
Amlan Biswas ◽  
...  
Keyword(s):  
1975 ◽  
Author(s):  
R. M. Housley ◽  
S. Geller ◽  
G. P. Espinosa
Keyword(s):  

1977 ◽  
Vol 14 (4) ◽  
pp. 684-706 ◽  
Author(s):  
Patrick J. C. Ryall ◽  
James M. Hall ◽  
J. Clark ◽  
T. Milligan

The detailed study of 455 basement samples from DSDP Leg 37 reveals magnetic properties, particularly inclinations and intensities, different from those commonly considered representative of Layer 2. Non-dipole inclinations are the most common. The deepest hole (582 m) has a vector average intensity of 24.3 × 10−4 emu cm−3 (24.3 × 10−1 A/m) and an inclination of only −14.5°. Induced magnetization never dominates and is usually much less than remanent magnetization, with Q ratio averaging 35 for basalts and 2.6 for plutonic rocks. Viscous magnetization acquisition constant, S, ranges widely from 0.001 to 1 × 10−4 emu cm−3 (0.001 to 1 × 10−1A/m), but is very rarely sufficient to cause VRM to dominate NRM.The major carrier of NRM is cation-deficient titanomagnetite produced by low-temperature oxidation of stoichiometric titantomagnetite. There is no trend of alteration with depth. All the magnetic properties are controlled by conditions within the individual basalt pillows or more massive units. A high degree of cation deficiency is associated with reduced NRM intensity, initial susceptibility, saturation magnetization, and VRM acquisition and increased MDF, Q ratio, and Curie point. Zones of low cation deficiency are presently found only in parts of massive units. With the exception of rare individual samples pillow sequences are highly oxidized throughout.A discussion is given of the kinds of ocean crust drilling and laboratory experiments required to solve the problems of the magnetic structure of Layer 2 as seen at the Leg 37 sites.


2020 ◽  
Vol 20 ◽  
pp. 100344 ◽  
Author(s):  
Zirui Jia ◽  
Zhenguo Gao ◽  
Kaichang Kou ◽  
Ailing Feng ◽  
Chuanhui Zhang ◽  
...  

2011 ◽  
Vol 21 (15) ◽  
pp. 5764 ◽  
Author(s):  
Glenn C. Mather ◽  
Susana García-Martín ◽  
Darja Benne ◽  
Clemens Ritter ◽  
Ulises Amador

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 5990
Author(s):  
Oleg V. Merkulov ◽  
Ruslan R. Samigullin ◽  
Alexey A. Markov ◽  
Mikhail V. Patrakeev

The electrical conductivity of La0.5−xSr0.5FeO3−δ, investigated as a function of the nominal cation deficiency in the A-sublattice, x, varying from 0 to 0.02, has demonstrated a nonlinear dependence. An increase in the x value from 0 to 0.01 resulted in a considerable increase in electrical conductivity, which was shown to be attributed mainly to an increase in the mobility of the charge carriers. A combined analysis of the defect equilibrium and the charge transport in La0.5−xSr0.5FeO3−δ revealed the increase in the mobility of oxygen ions, electrons, and holes by factors of ~1.5, 1.3, and 1.7, respectively. The observed effect is assumed to be conditioned by a variation in the oxide structure under the action of the cationic vacancy formation. It was found that the cation deficiency limit in La0.5−xSr0.5FeO3−δ did not exceed 0.01. A small overstep of this limit was shown to result in the formation of (Sr,La)Fe12O19 impurity, which even in undetectable amounts reduced the conductivity of the material. The presence of (Sr,La)Fe12O19 impurity was revealed by X-ray diffraction on the ceramic surface after heat treatment at 1300 °C. It is most likely that the formation of traces of the liquid phase under these conditions is responsible for the impurity migration to the ceramic surface. The introduction of a cation deficiency of 0.01 into the A-sublattice of La0.5−xSr0.5FeO3−δ can be recommended as an effective means to enhance both the oxygen ion and the electron conductivity and improve ceramic sinterability.


2020 ◽  
Vol 59 (13) ◽  
pp. 8744-8748 ◽  
Author(s):  
Takuro Dazai ◽  
Shintaro Yasui ◽  
Tomoyasu Taniyama ◽  
Mitsuru Itoh
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document