scholarly journals Nanostructured Manganite Films Grown by Pulsed Injection MOCVD: Tuning Low- and High-Field Magnetoresistive Properties for Sensors Applications

Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 605
Author(s):  
Voitech Stankevic ◽  
Nerija Zurauskiene ◽  
Skirmantas Kersulis ◽  
Valentina Plausinaitiene ◽  
Rasuole Lukose ◽  
...  
Keyword(s):  
High Field ◽  
Colossal Magnetoresistance ◽  
Film Plane ◽  
Magnetic Sensors ◽  
Sensor Applications ◽  
Operation Temperature ◽  
Low Field ◽  
Wide Range ◽  
Pulsed Injection ◽  
Crystal Quartz

The results of colossal magnetoresistance (CMR) properties of La0.83Sr0.17Mn1.21O3 (LSMO) films grown by pulsed injection MOCVD technique onto various substrates are presented. The films with thicknesses of 360 nm and 60 nm grown on AT-cut single crystal quartz, polycrystalline Al2O3, and amorphous Si/SiO2 substrates were nanostructured with column-shaped crystallites spread perpendicular to the film plane. It was found that morphology, microstructure, and magnetoresistive properties of the films strongly depend on the substrate used. The low-field MR at low temperatures (25 K) showed twice higher values (−31% at 0.7 T) for LSMO/quartz in comparison to films grown on the other substrates (−15%). This value is high in comparison to results published in literature for manganite films prepared without additional insulating oxides. The high-field MR measured up to 20 T at 80 K was also the highest for LSMO/quartz films (−56%) and demonstrated the highest sensitivity S = 0.28 V/T at B = 0.25 T (voltage supply 2.5 V), which is promising for magnetic sensor applications. It was demonstrated that Mn excess Mn/(La + Sr) = 1.21 increases the metal-insulator transition temperature of the films up to 285 K, allowing the increase in the operation temperature of magnetic sensors up to 363 K. These results allow us to fabricate CMR sensors with predetermined parameters in a wide range of magnetic fields and temperatures.

Low-Field Colossal Magnetoresistance in Manganite Tunnel Junctions

1997 ◽  
Vol 494 ◽  
Author(s):  
J. Nassar ◽  
M. Viret ◽  
M. Drouet ◽  
J. P. Contour ◽  
C. Fermon ◽  
...  
Keyword(s):  
Spin Polarization ◽  
High Field ◽  
Colossal Magnetoresistance ◽  
Tunnel Junctions ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Temperature Behaviour ◽  
Low Field ◽  
Tunnel Barriers ◽  
Magnetoresistance Ratio

ABSTRACTLarge magnetoresistance values are obtained on tunnel junctions epitaxially deposited by pulsed-laser deposition and consisting of ferromagnetic manganite La0.67Sr0.33MnO3 electrodes separated by various tunnel barriers: SrTiO3, PrBaCu2.8Ga0.2O7 and CeO2. The magnetoresistance can be decomposed into a low-field and a high-field contribution. The latter is attributed to the presence of canted interfacial manganite phases, as confirmed by the temperature behaviour of the resistance. A low-field magnetoresistance ratio of 450% below 100 Oe is obtained on a sample with a SrTiO3 barrier, indicating a spin polarization value in excess of 0.83 for the manganite.

scholarly journals High Field Linear Magnetoresistance Sensors with Perpendicular Anisotropy L10-FePt Reference Layer

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
X. Liu ◽  
Z. L. Song ◽  
R. Wang ◽  
Z. Y. Quan
Keyword(s):  
High Field ◽  
Film Plane ◽  
Magnetic Sensors ◽  
Perpendicular Anisotropy ◽  
Substrate Heating ◽  
Ferromagnetic Layers ◽  
Out Of Plane ◽  
Linear Magnetoresistance ◽  
Reference Layer

High field linear magnetoresistance is an important feature for magnetic sensors applied in magnetic levitating train and high field positioning measurements. Here, we investigate linear magnetoresistance in Pt/FePt/ZnO/Fe/Pt multilayer magnetic sensor, where FePt and Fe ferromagnetic layers exhibit out-of-plane and in-plane magnetic anisotropy, respectively. Perpendicular anisotropy L10-FePt reference layer with large coercivity and high squareness ratio was obtained by in situ substrate heating. Linear magnetoresistance is observed in this sensor in a large range between +5 kOe and −5 kOe with the current parallel to the film plane. This L10-FePt based sensor is significant for the expansion of linear range and the simplification of preparation for future high field magnetic sensors.

Nanomagnetic Ni-Array in Porous Silicon as a Possible Magnetic Field Sensor in the High Field Range up to 7 T

2005 ◽  
Vol 876 ◽  
Author(s):  
P. Granitzer ◽  
K. Rumpf ◽  
H. Krenn
Keyword(s):  
Magnetic Field ◽  
Porous Silicon ◽  
High Field ◽  
High Sensitivity ◽  
Steep Slope ◽  
Magnetic Field Sensor ◽  
Field Range ◽  
Sensor Applications ◽  
Low Field ◽  
Field Sensor

AbstractA highly doped n-type silicon wafer is anodized in an aqueous hydrofluoric acid solution to generate a porous silicon skeleton with a convenient morphology. After drying, the mesoporous sample is exposed to an electrodeposition process in which the pores are filled with the ferromagnetic metal Ni. Anodization and deposition of Ni lead to a ferromagnetic nanoscopic system which shows an interesting behaviour in the high field range (> 3 T). In addition to the expected low field switching below 500 Oe a second switching at fields of a few Tesla with a steep slope is also present. This feature with its extremely high sensitivity for changes of the external magnetic field gives rise to high magnetic field sensor applications based on a silicon technology.

Sequential assignment of NMR spectra of peptides at natural isotopic abundance with Zero and Ultra-Low Field-TOCSY

2021 ◽  
Author(s):  
Alexey S. Kiryutin ◽  
Ivan V. Zhukov ◽  
Fabien Ferrage ◽  
G Bodenhausen ◽  
Alexandra V. Yurkovskaya ◽  
...  
Keyword(s):  
High Field ◽  
Nmr Spectra ◽  
Correlation Spectroscopy ◽  
Sequential Assignment ◽  
Isotopic Abundance ◽  
Natural Isotopic Abundance ◽  
Low Field ◽  
Total Correlation ◽  
High Resolution Nmr ◽  
Novel Method

A novel method dubbed ZULF-TOCSY results from the combination of Zero and Ultra-Low Field (ZULF) with high-field, high-resolution NMR, leading to a generalization of the concept of total correlation spectroscopy...

scholarly journals Robust anomalous metallic states and vestiges of self-duality in two-dimensional granular In-InOx composites

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Xinyang Zhang ◽  
Bar Hen ◽  
Alexander Palevski ◽  
Aharon Kapitulnik
Keyword(s):  
Magnetic Field ◽  
Metallic Phase ◽  
Broadband Noise ◽  
Two Dimensional ◽  
Conventional Theory ◽  
Logarithmic Divergence ◽  
Self Duality ◽  
Low Field ◽  
Wide Range ◽  
Low Temperature Resistance

AbstractMany experiments investigating magnetic-field tuned superconductor-insulator transition (H-SIT) often exhibit low-temperature resistance saturation, which is interpreted as an anomalous metallic phase emerging from a ‘failed superconductor’, thus challenging conventional theory. Here we study a random granular array of indium islands grown on a gateable layer of indium-oxide. By tuning the intergrain couplings, we reveal a wide range of magnetic fields where resistance saturation is observed, under conditions of careful electromagnetic filtering and within a wide range of linear response. Exposure to external broadband noise or microwave radiation is shown to strengthen the tendency of superconductivity, where at low field a global superconducting phase is restored. Increasing magnetic field unveils an ‘avoided H-SIT’ that exhibits granularity-induced logarithmic divergence of the resistance/conductance above/below that transition, pointing to possible vestiges of the original emergent duality observed in a true H-SIT. We conclude that anomalous metallic phase is intimately associated with inherent inhomogeneities, exhibiting robust behavior at attainable temperatures for strongly granular two-dimensional systems.

Suppression of Ferromagnetism in EuxCa1-xB6

2012 ◽  
Vol 190 ◽  
pp. 97-100 ◽  
Author(s):  
V.V. Glushkov ◽  
A.V. Kuznetsov ◽  
I. Sannikov ◽  
A.V. Bogach ◽  
S.V. Demishev ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Curie Temperature ◽  
Single Crystals ◽  
Effective Magnetic Moment ◽  
Paramagnetic State ◽  
Low Field ◽  
Wide Range ◽  
Free Ion ◽  
The Eu

We report the magnetic properties of EuxCa1-xB6 single crystals (0.756x1) studied in the wide range of temperatures (1.8-300 K) and magnetic fields (up to 50 kOe). It was found that low field magnetic susceptibility χ (T) follows the Curie-Weiss law χ~(T-Θp)-1 at high temperatures for all the concentrations studied. The effective magnetic moment of the Eu2+ ion estimated from the data diminishes from the free ion value μeff7.93μB (μB - Bohr magneton) for x=1 to μeff7.3μB for x=0.756. A universal behavior of magnetic susceptibility χ~(T-Θ)-α (α=1.5) is detected close to the Curie temperature TC in the paramagnetic state at both metallic (x>xC~0.8) and dielectric (xC.

Comparison of High-Field-Strength Versus Low-Field-Strength MRI of the Shoulder

2003 ◽  
Vol 181 (5) ◽  
pp. 1211-1215 ◽  
Author(s):  
Thomas Magee ◽  
Marc Shapiro ◽  
David Williams
Keyword(s):  
Field Strength ◽  
High Field ◽  
High Field Strength ◽  
Low Field

scholarly journals Effect of Sintering Temperature on Metal-Insulator Phase Transition in La1-xCaxMnO3 Perovskites

2020 ◽  
Vol 2 (1) ◽  
pp. 37-42
Author(s):  
Arunachalam M ◽  
Thamilmaran P ◽  
Sakthipandi K
Keyword(s):  
Phase Transition ◽  
Bulk Modulus ◽  
Sintering Temperature ◽  
Magnetic Sensors ◽  
Temperature Dependent ◽  
Metal Insulator ◽  
Wide Range ◽  
Different Temperatures ◽  
Insulator Phase Transition

Lanthanum calcium based perovskites are found to be advantageous for the possible applications in magnetic sensors/reading heads, cathodes in solid oxide fuel cells, and frequency switching devices. In the present investigation La0.3Ca0.7MnO3 perovskites were synthesised through solid state reaction and sintered at four different temperatures such as 900, 1000, 1100 and 1200˚ C. X-ray powder diffraction pattern confirms that the prepared La0.3Ca0.7MnO3 perovskites have orthorhombic structure with Pnma space group. Ultrasonic in-situ measurements have been carried out on the La0.3Ca0.7MnO3 perovskites over wide range of temperature and elastic constants such as bulk modulus of the prepared La0.3Ca0.7MnO3 perovskites was obtained as function of temperature. The temperature-dependent bulk modulus has shown an interesting anomaly at the metal-insulator phase transition. The metal insulator transition temperature derived from temperature-dependent bulk modulus increases from temperature 352˚ C to 367˚ C with the increase of sintering temperature from 900 to 1200˚ C.

scholarly journals Observing the impossible – in situ observations of hail trajectories using the HailSonde

2021 ◽  
Author(s):  
Joshua Soderholm
Keyword(s):  
Science Fiction ◽  
Sensor Applications ◽  
New Science ◽  
Prototype Development ◽  
Real Science ◽  
Wide Range ◽  
Micro Sensor ◽  
Battery Technology ◽  
Aviation Risk ◽  
Ground Impact

<p>From the early stages of hailstone growth to the ground-impact finale, a trajectory is taken by each hailstone through the parent hailstorm. Larger hailstones form as their trajectory takes them into regions of the storm that are more favorable for growth, while others may miss out entirely. Simulation-based studies have shown that interactions between the hailstone fall speed, aerodynamics, storm winds (which continue to change along the trajectory and with new growth) can take hailstones on a myriad of different trajectories. Despite improvements in radar technology over the last 20 years, operational hail analysis techniques have changed little, and do not consider trajectories, leaving a high degree of uncertainty when estimating ground impact.</p> <p>Case studies have demonstrated that trajectory information provides significant improvements to hail impact mapping and nowcasting services, but the lack of robust<br />observational datasets to leverage new radar technology and verify trajectories prevents the transition of this new science into operations. The follow proposal presents an innovative approach to measuring trajectories within a hailstorm using hailstone-shaped probes called “HailSondes”. Recent advances in low-energy telemetry, battery technology and electronics miniaturization are combined to make this new sensor possible, which, until recently, was the realm of fantasy for meteorologists (e.g., the 1996 Hollywood classic “Twister” imagined a similar sensors for observing tornadoes). The design challenges, simulations, prototype development and deployment of HailSondes are discussed.</p> <p>HailSonde measurements will provide critical validation for the practical application radarderived trajectories for hailstorm analysis and nowcasting, supporting the transition to future hail services and benefiting a wide range of sectors from aviation, risk management, transport and public safety. This transition from science fiction into real science signifies extraordinary potential for further remote micro-sensor applications in the future. </p>

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