Nanorods of Dy Modified BiFeO3 for Multifunctional Device Applications

2011 ◽  
Vol 1303 ◽  
Author(s):  
M. Mandal ◽  
S. P. Duttagupta ◽  
V. R. Palkar
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Applied Electric Field ◽  
Room Temperature ◽  
Lateral Displacement ◽  
Ferroelectric Properties ◽  
Magnetic Domain ◽  
Base Material ◽  
Coupling Behavior ◽  
Device Applications

ABSTRACTWe have developed material (Bi0.7Dy0.3FeO3)(BDFO) which exhibits the multiferroic behavior at room temperature with significant coupling in bulk as well as thin films. If these properties could be fashioned in nano rods, implementation in devices could be certainly more prominent and straight forward. We have therefore used vertically aligned arrays of silicon rods (~5 μm in length and ~ 500 nm in diameter) as base material to direct the growth of BDFO in rod form. BDFO is deposited on the surface of Si rods by using pulsed laser deposition technique. These BDFO/Si rods are then separated from the support, dispersed into propanol and transferred onto SiO2/Si substrates for testing. X-ray diffraction (XRD) results indicate presence of phase pure BDFO layer on Si rods. Saturation observed at room temperature in magnetic and ferroelectric hysteresis loops confirm the coexistence of ferromagnetic and ferroelectric properties. Change in ferroelectric polarization measured on single rod in the presence of applied magnetic field suggests the coupling behavior between two order parameters. Moreover, change in magnetic domain pattern of BDFO rods associated with applied electric field further supports the presence of coupling behavior in both ways. The vertical and lateral displacement occurring in BDFO/Si rods with applied electric field helps to confirm their piezoresponce behavior. BDFO/Si nanorods with multifunctional properties could find variety of novel device applications with flexibility and simplicity in operation. It might include single rod power generation by means of applied stress or magnetic field.

Optical properties in GaAs/AlGaAs semiparabolic quantum wells by the finite difference method: Combined effects of electric field and magnetic field

2018 ◽  
Vol 32 (13) ◽  
pp. 1850159 ◽  
Author(s):  
Ru-Yu Yan ◽  
Jian Tang ◽  
Zhi-Hai Zhang ◽  
Jian-Hui Yuan
Keyword(s):  
Magnetic Field ◽  
Optical Properties ◽  
Electric Field ◽  
Quantum Wells ◽  
Applied Electric Field ◽  
Differential Method ◽  
Optical Rectification ◽  
Intersubband Transitions ◽  
Energy Eigenvalues ◽  
Device Applications

In the present work, the optical properties of GaAs/AlGaAs semiparabolic quantum wells (QWs) are studied under the effect of applied electric field and magnetic field by using the compact-density-matrix method. The energy eigenvalues and their corresponding eigenfunctions of the system are calculated by using the differential method. Simultaneously, the nonlinear optical rectification (OR) and optical absorption coefficients (OACs) are investigated, which are modulated by the applied electric field and magnetic field. It is found that the position and the magnitude of the resonant peaks of the nonlinear OR and OACs can depend strongly on the applied electric field, magnetic field and confined potential frequencies. This gives a new way to control the device applications based on the intersubband transitions of electrons in this system.

scholarly journals Current-Induced Spin Photocurrent in GaAs at Room Temperature

Sensors ◽  
2022 ◽  
Vol 22 (1) ◽  
pp. 399
Author(s):  
Yang Zhang ◽  
Yu Liu ◽  
Xiao-Lan Xue ◽  
Xiao-Lin Zeng ◽  
Jing Wu ◽  
...  
Keyword(s):  
Electric Field ◽  
Spin Polarization ◽  
Applied Electric Field ◽  
Room Temperature ◽  
Polarization Direction ◽  
Applied Bias ◽  
Applied Bias Voltage ◽  
Sample Plane ◽  
Bulk Gaas ◽  
Circularly Polarized

Circularly polarized photocurrent, observed in p-doped bulk GaAs, varies nonlinearly with the applied bias voltage at room temperature. It has been explored that this phenomenon arises from the current-induced spin polarization in GaAs. In addition, we found that the current-induced spin polarization direction of p-doped bulk GaAs grown in the (001) direction lies in the sample plane and is perpendicular to the applied electric field, which is the same as that in GaAs quantum well. This research indicates that circularly polarized photocurrent is a new optical approach to investigate the current-induced spin polarization at room temperature.

INFLUENCE OF THE MAGNETIC FIELD ON THE TRANSVERSE RUNAWAY THRESHOLD

2007 ◽  
Vol 21 (10) ◽  
pp. 1715-1720 ◽  
Author(s):  
NANA METREVELI ◽  
ZAUR KACHLISHVILI ◽  
BEKA BOCHORISHVILI
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Electric Fields ◽  
Applied Electric Field ◽  
Nonlinear Oscillations ◽  
Hot Electrons ◽  
Total Field ◽  
Practical Applications ◽  
Energy And Momentum ◽  
The Magnetic Field

The transverse runaway (TR) is a phenomenon whereby for a certain combination of energy and momentum scattering mechanisms of hot electrons, and for a certain threshold of the applied electric field, the internal (total) field tends to infinity. In this work, the effect of the magnetic field on the transverse runaway threshold is considered. It is shown that with increasing magnetic field, the applied critical electric fields relevant to TR decrease. The obtained results are important for practical applications of the TR effect as well as for the investigation of possible nonlinear oscillations that may occur near the TR threshold.

INVESTIGATION OF LEAKAGE CURRENT BEHAVIOR OF Pt/Bi0.975La0.025Fe0.975Ni0.025O3/Pt CAPACITOR MEASURED AT DIFFERENT TEMPERATURES

2014 ◽  
Vol 21 (02) ◽  
pp. 1450029 ◽  
Author(s):  
XIU HONG DAI ◽  
HONG DONG ZHAO ◽  
LEI ZHANG ◽  
HUI JUAN ZHU ◽  
XIAO HONG LI ◽  
...  
Keyword(s):  
Electric Field ◽  
Leakage Current ◽  
Applied Electric Field ◽  
Conduction Mechanism ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Ohmic Behavior ◽  
Different Temperatures ◽  
Limited Conduction ◽  
Current Behavior

Polycrystalline Bi 0.975 La 0.025 Fe 0.975 Ni 0.025 O 3 (BLFNO) film is fabricated on Pt / Ti / SiO 2/ Si (111) substrate by sol–gel method. It is found that the well-crystallized BLFNO film is polycrystalline, and the Pt / BLFNO / Pt capacitor possesses good ferroelectric properties with remnant polarization of 74 μC/cm2 at electric field of 833 kV/cm. Moreover, it is also found that the leakage current density of the Pt / BLFNO / Pt capacitor increases with the increase of measurement temperature ranging from 100 to 300 K. The leakage density of the Pt / BLFNO / Pt capacitor satisfies space-charge-limited conduction (SCLC) at higher electric field and shows little dependence on voltage polarity and temperature, but shows polarity and temperature dependence at lower applied electric field. With temperature increasing from 100 to 300 K at lower applied electric field, the most likely conduction mechanism is from Ohmic behavior to SCLC for positive biases, but no clear dominant mechanism for negative biases is shown.

scholarly journals The modified magnetodielectric response in KNN-CZFMO based particulate multiferroic composite system

2020 ◽  
Vol 10 (05) ◽  
pp. 2050024 ◽  
Author(s):  
Kulwinder Kaur ◽  
Mandeep Singh ◽  
Jaspal Singh ◽  
Sanjeev Kumar
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Room Temperature ◽  
Research Work ◽  
Hysteresis Loops ◽  
Magnetic Ordering ◽  
X Ray Diffraction ◽  
Universal Power Law ◽  
Multiferroic Composite ◽  
Magnetic Dielectric

Lead-free multiferroic composites of 1[Formula: see text](K[Formula: see text]Na[Formula: see text]NbO[Formula: see text](Co[Formula: see text]Zn[Formula: see text](Fe[Formula: see text]Mn[Formula: see text]O4 (KNN-CZFMO), where [Formula: see text]= 0.0, 0.1, 0.2, 0.3, 0.4, 0.5 and 1.0, have been investigated for their structural, morphological, electrical, magnetic, dielectric and magneto-dielectric properties. Presence of KNN and CZFMO crystal structure in each composite has been confirmed from X-ray diffraction analysis (XRD). Cuboidal-shaped grains of KNN and spherical-shaped grains of CZFMO have been observed by scanning electron microscopy (SEM). The room temperature ferroelectric behavior as confirmed by polarization versus electric field ([Formula: see text]–[Formula: see text] hysteresis loops has been found to be decreasing with increasing CZFMO concentration. Increasing magnetic ordering with the increase in CZFMO concentration in the prepared composites has been observed by magnetization versus magnetic field ([Formula: see text]–[Formula: see text] hysteresis loops. The electrical conductivity of composites has been studied using Jonscher’s universal power law. The room temperature dielectric constant ([Formula: see text] and dielectric loss (tan [Formula: see text] have been observed to decrease with the increase in the frequency of the applied external electric field. The dielectric relaxation behavior has been observed using curve fitting analysis via the Havriliak–Negami relaxation model. Maximum value of the magnetodielectric (MD) effect [Formula: see text]−11% at a frequency of 1 kHz with the applied magnetic field of 1 T has been achieved for 0.9 KNN−0.1 CZFMO ([Formula: see text]= 0.1) composite in the present research work.

scholarly journals Ferroelectric and Electrical Properties Optimization of Mg-doped BiFeO3 Flexible Multiferroic Films

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1173
Author(s):  
Der-Yuh Lin ◽  
Hone-Zern Chen ◽  
Ming-Cheng Kao ◽  
Pei-Li Zhang
Keyword(s):  
Electric Field ◽  
Leakage Current ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Storage Device ◽  
Bifeo3 Film ◽  
Device Applications ◽  
Multiferroic Films ◽  
Current Densities ◽  
Leakage Current Mechanism

Bi1-xMgxFeO3 (BMFO, x = 0, 0.02, 0.04, 0.06 and 0.08) multiferroic films were directly synthesized on flexible stainless steel (FSS), save the bottom electrode process, by means of sol–gel spin-coating technology. The effects of different bending conditions on ferroelectric, dielectric and leakage-current properties of BMFO films were investigated. The leakage-current densities of BiFeO3 (BFO, x = 0) and BMFO (x = 0.06) films were 5.86 × 10−4 and 3.73 × 10−7 A/cm2, which shows that the BMFO (x = 0.06) has more than three orders of magnitude lower than that of BFO film. The residual polarization (2 Pr) can be enhanced from 120 to 140 μC/cm2. The proper doping of Mg in BiFeO3 film could provide an effective method for reducing the leakage-current values as well as boosting the ferroelectric properties. In this study, the leakage-current mechanism of low electric field and high electric field of BMFO film is analyzed and established. In addition, the flexible BMFO film maintains practical ferroelectric and leakage-current properties at retention time of 106 s under different symmetry bending conditions. These results indicate that the BFMO film will be very practical in opto-electronic and storage device applications.

Ferroelectricity and phase transitions in In2Se3 van der Waals material

Nanoscale ◽  
2020 ◽  
Vol 12 (44) ◽  
pp. 22688-22697
Author(s):  
Maryam Soleimani ◽  
Mahdi Pourfath
Keyword(s):  
Phase Transitions ◽  
Electric Field ◽  
Applied Electric Field ◽  
Room Temperature ◽  
Van Der Waals ◽  
Out Of Plane

Van der Waals layered α-In2Se3 has shown out-of-plane ferroelectricity down to the bilayer and monolayer thicknesses at room temperature that can be switched by an applied electric field.

Functional oxide films with engineered ferroelectric properties

2013 ◽  
Vol 1507 ◽  
Author(s):  
R. Wördenweber ◽  
T. Ehlig ◽  
J. Schubert ◽  
R. Kutzner ◽  
E. Hollmann
Keyword(s):  
Electric Field ◽  
Room Temperature ◽  
Dipole Moments ◽  
Ferroelectric Properties ◽  
Field Direction ◽  
Complex Dielectric Constant ◽  
Electric Field Direction ◽  
Relaxation Experiments ◽  
Polar Nanoregions ◽  
The Given

ABSTRACTThe ferroelectric properties of anisotropically strained SrTiO3 films are analyzed by detailed measurements of the complex dielectric constant as function of temperature, frequency, bias voltage and electric field direction. The strain induces a relaxor-ferroelectric phase that persists up to room temperature. However, transition temperature and ferroelectric properties strongly depend on the orientation of the electric field and therefore on the amount of structural strain in the given electric field direction. Frequency and time dependent relaxation experiments reveal the presence and properties of polar nanoregions with randomly distributed directions of dipole moments in the film.

Positron annihilation in methane

1977 ◽  
Vol 55 (3) ◽  
pp. 235-239 ◽  
Author(s):  
A. C. Mao ◽  
D. A. L. Paul
Keyword(s):  
Electric Field ◽  
Positron Annihilation ◽  
Applied Electric Field ◽  
Room Temperature ◽  
Positive Energy ◽  
Annihilation Rate ◽  
Linear Region ◽  
Gas Density ◽  
Single Level ◽  
Made In

Measurements of positron annihilation rates at room temperature under the influence of an applied electric field have been made in methane at different pressures. The experiments were all carried out in the linear region in which the annihilation rate is accurately proportional to gas density. We find Zeff = 142.7 ± 2.0 at 21 °C and zero electric field. At 1000 Torr Zeff decreases linearly with the electric field, the gradient being about 2.5 × 10−2 per (V cm−1 atm−1) at that temperature. The results repudiate the idea of a positive energy single level Breit–Wigner resonance as being responsible for the high value of Zeff, and in this sense are in agreement with the findings of McNutt, Summerour, Ray, and Huang.

Sign in / Sign up

Export Citation Format

Share Document