A5055740398- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- Multiferroics and related materials
- Rare-earth and actinide compounds
- Ferroelectric and Piezoelectric Materials
- Nuclear materials and radiation effects
- Microwave Dielectric Ceramics Synthesis
- Acoustic Wave Resonator Technologies
- Thermal Expansion and Ionic Conductivity
- Physics of Superconductivity and Magnetism
- Magnetic Properties of Alloys
- Catalytic Processes in Materials Science
- Nuclear Materials and Properties
- Advanced ceramic materials synthesis
- Crystal Structures and Properties
- Glass properties and applications
- X-ray Diffraction in Crystallography
- Dental materials and restorations
- Electronic and Structural Properties of Oxides
- Nuclear Physics and Applications
- Silicon and Solar Cell Technologies
- Hydrocarbon exploration and reservoir analysis
- Inorganic Fluorides and Related Compounds
- Advancements in Solid Oxide Fuel Cells
- Coal Properties and Utilization
Bhabha Atomic Research Centre
2011-2021
Homi Bhabha National Institute
2020-2021
Variable Energy Cyclotron Centre
2009-2012
Manipur University
2011
S.N. Bose National Centre for Basic Sciences
2011
Bhabha Atomic Research Center Hospital
2003-2006
Saurashtra University
2004
Tata Institute of Fundamental Research
2004
Solid State Physics Laboratory
1997
High-temperature relaxor ferroelectric behavior (Tm ∼ 550 K) is reported for the rutile-based oxide, FeTiTaO6. Our investigations of structure and dielectric properties MTiTaO6 (M = Al, Cr, Fe) have revealed that all oxides possess disordered rutile but only iron member shows a strong effect. The new material lead-free it based on structure, unlike conventional relaxors which are mostly derived from perovskite structure.
The meta-stable orthorhombic phase of lead meta-niobate (PbNb2O6), as obtained by quenching, is piezoelectric, but difficult to prepare in pure state a few competing phases like the non-piezoelectric rhombohedral PbNb2O6 tend form during preparation. However, it can have an attractively high Curie temperature above 570°C. High piezoelectric sensors are desirable for imaging and other applications certain industrial research sectors. Presently, both been synthesized single samples shown here...
The effect of substituting La with Dy in the ferromagnetic perovskite ${\mathrm{La}}_{0.7}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3}$ has been studied series $({\mathrm{La}}_{(1\ensuremath{-}x)}{\mathrm{Dy}}_{x}{)}_{0.7}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3}$ $(x=0,$ 0.114, 0.243, and 0.347). Magnetic transport properties have measured using ac susceptibility, dc magnetization, neutron-depolarization, neutron-diffraction, resistivity techniques. These studies show that an increase concentration...
Hydroxyapatite (HA) nanoparticles have been synthesized using ortho-phosphoric acid as the source of PO43− ions, and calcium chloride, suitably complexed with triethanolamine, source. The effect temperature on morphology product has investigated. chemical compositions samples established through Fourier transform infrared spectroscopy. This study reveals that A-type B-type carbonate substitution are present in HA concentration ions decrease rise temperature. Morphological analyses by TEM...
The neutron powder diffractometers and the polarized spectrometer at Dhruva reactor, Trombay have been used extensively for magnetic studies of several class important materials, suc...
A high piezoelectric transition temperature is indicated for present orthorhombic samples of lead meta-niobate (PbNb2O6) by the value (Tm) at which real part (ϵ′) electrical permittivity peaks. It 573 to 580°C. The imaginary component (ϵ″) increases sharply these temperatures. Cooling run after heating 700°C gives changed values ϵ′ and ϵ″ Tm. Present work reports impedance spectroscopy (up over 20 Hz 5.5 MHz) Differential Scanning Calorimetry or DSC on pure phase, and, first time,...
A high-temperature neutron diffraction study has been carried out on La(0.75)Sr(0.25)CrO(3) compound in the temperature range 300-1400 K. On doping parent LaCrO(3) with Sr at La site, orthorhombic (Pbnm) to rhombohedral ([Formula: see text]) structural transition shifts lower temperatures. From quantitative Rietveld analysis it is found unequivocally that there a two-phase coexistence (orthorhombic and phases ∼89 11 weight%, respectively) 300-470 K three-phase (with new cubic phase space...
We embarked on a study of Scandium (Sc) doped (onto Ga site) gallium ferrite (GaFeO3) and found remarkable magnetic properties. In both as well parent compounds, there were three types Fe3+ ions (depending the symmetry) with structure conforming to space group Pna21 (Sp. Grp. No. 33) below room temperature down 5 K. also that all occupy octahedral sites, carry high spin moment. For higher Sc substituted sample (Ga1−xScxFeO3: x = 0.3), canted ordered state is found. Spin-phonon coupling Néel...
The La-2125 type La2-xDyxCa2xBa2Cu4+2xOz (0.1 < x 0.5; LDBO) compounds have been synthesized and studied for their structural superconducting properties by room temperature neutron diffraction, high field dc magnetization, four-probe resistivity iodometric double titration. Rietveld analysis of the diffraction data reveals tetragonal structure all samples, which crystallizes into La-123 in P4/mmm space group. Iodometric titrations were performed to determine oxygen content values calculate...
Abstract Quenching induced orthorhombic distortion makes quenched (Q) lead meta‐niobate (PbNb 2 O 6 ), to be called PNQ, piezoelectric with a high Curie temperature (T c ) of 570 °C, while its slow‐cooled rhombohedral phase, PNS, remains non‐piezoelectric. So, positron lifetime components (( i and I have been measured for these pellets also tetragonal BaTiO 3 or BT = 127 °C), prepared by 6h (6+4)h firings. In our 3‐component fit, ( 1 is different in PNQ (152.9 ± 9.8) ps PNS (136.6 9.2) ps....
Neutron diffraction studies were carried out to ascertain the structural details of composition Ce 0.5 Nd O 1.750 . The structure was unequivocally found be that C-type cubic. refinement on an F-type cubic lattice unacceptable because high R values. Selected bond distances are also being reported. In addition, neutron a typical defective 0.75 0.25 1.875 out.