A5040853661- Physics of Superconductivity and Magnetism
- Drug Solubulity and Delivery Systems
- Advanced Drug Delivery Systems
- Analytical Methods in Pharmaceuticals
- Magnetic properties of thin films
- Analytical Chemistry and Chromatography
- Advanced Condensed Matter Physics
- Metallic Glasses and Amorphous Alloys
- Glass properties and applications
- Phase-change materials and chalcogenides
- Advancements in Transdermal Drug Delivery
- Quantum and electron transport phenomena
- Theoretical and Computational Physics
- Material Dynamics and Properties
- Antibiotics Pharmacokinetics and Efficacy
- Superconducting Materials and Applications
- Liquid Crystal Research Advancements
- Surface and Thin Film Phenomena
- High-pressure geophysics and materials
- Superconductivity in MgB2 and Alloys
- Magnetic and transport properties of perovskites and related materials
- Iron-based superconductors research
- Copper Interconnects and Reliability
- Crystallization and Solubility Studies
- Computational Drug Discovery Methods
Hindu College of Pharmacy
2013-2024
Savitribai Phule Pune University
2019-2024
PES University
2019
Jawaharlal Nehru Technological University, Hyderabad
2019
Marathwada Mitra Mandal's College of Pharmacy
2018
Mitra Biotech (India)
2018
Modern College of Business and Science
2014-2015
Birla Institute of Technology, Mesra
2014
NIMS University
2013
Brookhaven National Laboratory
2003-2010
The critical current densities across grain boundaries have been measured as a function of misorientation angle in the basal plane bicrystals $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$. For small angles, ratio grain-boundary density to bulk is roughly proportional inverse angle; for large this saturates value about $\frac{1}{50}$. These results imply that achieving high degree texture both normal and within important obtaining very...
Previous work on the superconducting transport properties of individual grain boundaries in thin-film bicrystals ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ has been extended to provide a more comprehensive picture their weak-link characteristics. Grain with three different geometries have studied; all types are essentially identical, which implies that poor coupling between grains is result intrinsic structural disorder at boundary. The grain-boundary critical current...
We have grown epitaxial films of the ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{x}}$ compound on ${\mathrm{SrTiO}}_{3}$ substrates. The superconducting critical current in these at 77 K is excess ${10}^{5}$ A/${\mathrm{cm}}^{2}$ and 4.2 ${10}^{6}$ A/${\mathrm{cm}}^{2}$.
We have made the first direct measurements of critical current density individual grain boundaries and their adjoining grains in ${\mathrm{Y}}_{1}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ superconducting films. The boundary was always found to be less than either two grains. magnetic field dependence indicates that they are comprised regions weak strong Josephson coupling. A single also used build operate a simple dc SQUID....
The temperature and magnetic field dependences of the critical-current density superconducting Y${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ films have been determined from transport measurements across individual [001] tilt boundaries within single grains. results provide evidence that basal-plane ${J}_{f}$ is limited by flux creep. In contrast, $I\ensuremath{-}V$ characteristics grain-boundary ${J}_{c}$ are consistent with a superconductor-normal-superconductor-type weak-link...
It has been demonstrated that perpendicular uniaxial anisotropy and compensation points in the vicinity of room temperature can be obtained amorphous thin films rare-earth—transition-metal alloys. The magneto-optic properties these are reported, it is shown a remarkably good signal-to-noise ratio thermomagnetically written film.
We have fabricated superconducting quantum interference devices (dc SQUID’s) from thin films of the oxide YBa2Cu3Oy. The were made by first lithographically patterning an ion implant mask containing a 40 μm loop and two 17-μm-wide weak links over ∼1-μm-thick film. Ion implantation was then used to destroy superconductivity in film surrounding device without actually removing material, resulting completely planar structure for SQUID’s. SQUID’s operated temperature range 4.2 68 K. flux...
We have found that sputtered amorphous films of Gd-Co and Gd-Fe perpendicular magnetic anisotropy. The demagnetized domain configuration consists stripe domains, bubble domains were nucleated in an applied field. By controlling the sputtering conditions, with a wide variety properties obtained.
The effect of grain growth on stresses in films is discussed. Grain generally leads to stress relaxation when the film under a compressive stress. When initial size below critical value, can occur by normal boundary migration and generates tensile plane film. proceeds until particular reached, at which sum strain energy surface minimized. Further if plastic flow relieves some energy. above size, there no minimum vs relationship, infinite migration. In presence impurities, apparently...
We used near-edge x-ray absorption fine structure (NEXAFS) spectroscopy to link the orientational bond order at three carbonaceous surfaces-rubbed polyimide, ion beam-irradiated and diamondlike carbon films-with direction of liquid crystal (LC) alignment on these surfaces. show that, in general, LC can be created any substrate by inducing its surface. Our results form scientific basis for layers consisting amorphous films which near surface is induced a directional low-energy beam.
Studies of superconductivity in thin films La-Sr-Cu-O and Y-Ba-Cu-O have resulted samples completely superconducting at 87 K with onsets as high 97 K. The high-${T}_{c}$ materials show a strong Meissner effect which agrees the temperature dependence resistance. Critical current densities excess 300 A/${\mathrm{cm}}^{2}$ been measured close to ${T}_{c}$ Y-based materials.
The effect of thermally activated phase slippage (TAPS) in ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ grain-boundary Josephson junctions has been studied. TAPS found to be responsible for the dc noise voltage superimposed on current near transition temperature. Because reduced coupling energy junctions, which is caused by a superconducting order parameter at interface, present over considerable temperature range. implications applicability high-${\mathrm{T}}_{\mathrm{c}}$ are outlined.
We propose a way to measure the interference associated with two superconductors ${\mathit{d}}_{\mathit{x}}^{2}$-${\mathit{y}}^{2}$ symmetry coupled by Josephson weak link. An experimental realization shows no effects in superconducting ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ film. The results are consistent s-wave symmetry.
We have fabricated YBa2Cu3O7−δ grain boundary junction dc superconducting quantum interference devices (SQUIDs) with a square washer geometry design. The SQUIDs were formed in c-axis oriented epitaxial films single of predetermined nature. These show perfectly periodic voltage-flux characteristics without hysteresis from 4.2 to 87 K. At 77 K intrinsic energy sensitivities 1.5×10−30 and 3.0×10−30 J/Hz at 10 kHz obtained for 60 110 pH SQUIDs, respectively. sensitivity limited by 1/f noise Hz...
A model for hillock growth in thin films such as those of lead and tin is developed. It proposed that a form stress relaxation which atomic species diffuse along the film-substrate interface to base hillock. The latter extrudes out grain boundaries connecting it rest film. stability kinetics this process are considered. Taking into account Nabarro-Herring diffusion creep parallel mechanism observations an incubation period effects film thickness on density accounted for. In addition, lateral...
We have computer simulated the structure of thin amorphous films grown from a vapor. Our hard-sphere model shows that structural anisotropy and voids are natural occurrence deposition process. The amount unfilled space (voids) been studied as function angle incidence vapor stream upon substrate.
Recent experience has shown that certain metal alloys can be put into glass form by rapid melt-quenching or various condensation processes. Models for the nature and structure of these glasses are surveyed to quite parallel those already developed more common nonmetallic glasses. The rather unique magnetic, superconducting, mechanical properties technical potential metallic also discussed.
The mucoadhesive gel formulations are helpful to prolong the residence time at nasal absorption site and thereby facilitate uptake of drug. Sumatriptan succinate has oral bioavailability 15% undergoes hepatic metabolism, hence it is suitable for administration.The objective investigation was develop a in situ improve sumatriptan succinate.Deacetylated gellan gum used as gelling agent. In formulated by ion activation mechanism simulated fluid. A 3(2) factorial design found optimize batch....
A low temperature magnetic force microscope has been applied to spatially resolve single vortices in an epitaxially grown YB${\mathrm{a}}_{2}$C${\mathrm{u}}_{3}$ ${\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ thin film at 77 K. disordered vortex arrangement is observed, and the are strongly pinned. The observed phase expected be truly superconducting due strong pinning.
We have measured 1/f noise of single-grain-boundary junctions in superconducting ${\mathrm{Y}}_{1}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ epitaxial films. The origin is identified and the data are used to rule out recent suggestions for new mechanisms which generate noise. Using ozone annealing, both critical current density grain boundary were found improve. However, persistence Josephson coupling suggest that oxygen...
We obtain the a-b plane infrared conductivity of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ from temperature-dependent reflectivity spectra crystals and films with ${T}_{c}$\ensuremath{\simeq}92 K. The normal state is characterized by a free-carrier band an enhanced low-frequency mass frequency-dependent scattering rate, which indicate coupling to excitation spectrum characteristic frequency scale ${\ensuremath{\omega}}_{c}$\ensuremath{\lesssim}700...
We have found that the product of critical current and resistance a grain-boundary junction scale with boundary. This scaling is observed to hold for variety samples prepared by evaporation or laser ablation whose density varies three orders magnitude.
Twist boundaries have been observed on {001} surfaces between crystals of MgO and CdO smoke. Measurements the angles twist across several hundred these revealed preferences for at 16.5°, 22.6°, 37.3° in 22.8°, 28.5°, 37.1° CdO. These agree with those predicted by coincidence site model to within accuracy measurement.