A5050305479- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Multiferroics and related materials
- Electronic and Structural Properties of Oxides
- Physics of Superconductivity and Magnetism
- Crystal Structures and Properties
- Machine Learning in Materials Science
- X-ray Diffraction in Crystallography
- Magnetic properties of thin films
- Advanced Thermoelectric Materials and Devices
- Ferroelectric and Piezoelectric Materials
- ZnO doping and properties
- Supply Chain Resilience and Risk Management
- Perovskite Materials and Applications
- Rare-earth and actinide compounds
Homi Bhabha National Institute
2023-2024
Roma Tre University
2023-2024
Institute of Physics, Bhubaneshwar
2023-2024
Indian Association for the Cultivation of Science
2016-2023
We present an experimental investigation of the magnetic ground state in <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:msub><a:mi>Ba</a:mi><a:mn>4</a:mn></a:msub><a:msub><a:mi>NbIr</a:mi><a:mn>3</a:mn></a:msub><a:msub><a:mi mathvariant="normal">O</a:mi><a:mn>12</a:mn></a:msub></a:mrow></a:math>, a fractional valent trimer iridate. X-ray absorption and photoemission spectroscopy show that Ir valence lies between <c:math...
Abstract The magnetic ground states in highly ordered double perovskites LaSr 1− x Ca NiReO 6 ( = 0.0, 0.5, 1.0) are studied view of the Goodenough-Kanamori rules superexchange interactions this paper. In LaSrNiReO , Ni and Re sublattices found to exhibit curious separately, but no long range ordering is achieved. transition at ~255 K identified with independent sublattice ordering. Interestingly, tuned by modifying Ni-O-Re bond angles through doping. Upon doping, start display a...
The structural, magnetic and dielectric properties of the hexagonal four-layered form SrMnO<sub>3</sub> along with its fluorinated counterpart have been investigated.
Perovskites containing barium metal at the $A$ site often take up unusual hexagonal structures having more than one type of possible sites for $B$ cation to occupy. This opens various different $B\text{\ensuremath{-}}B$- or $B$-O-$B$-type connectivities and consequent physical properties which are naturally missing in cubic perovskites. ${\mathrm{BaRuO}}_{3}$ is such system where doping Ru $(4{d}^{4})$ by other transition metals $({M}^{n+})$ creates similar conditions, giving rise $M$-Ru...
Brownmillerite structure is derived from an ordered arrangement of oxygen vacancies within a perovskite structure, where alternating stacked layers tetrahedral and octahedral units are formed with vacancy channels aligned in the layer. Naturally it becomes important proposition to attempt anion engineering such structures. Accordingly, we have synthesized oxyfluoride brownmillerite Ca2Fe2O5 by low temperature fluorination technique poly(vinylidene fluoride) as fluorinating agent. The global...
Four distinct classes of multiferroics are usually being discussed in the literature, which ferroelectricity is respectively driven by electronic lone pairs, geometry, charge ordering, and magnetism. Each class has its own shortcomings for technological applications. Here, through a combined experimental theoretical investigation, we propose mechanism to achieve multiferroicity single phase engineering anionic network creating local geometric distortions fluorinated, vacancy-ordered...
Strong spin-orbit coupling (SOC) in iridates has long been predicted to lead exotic electronic and magnetic ground states. Ba2YIrO6 (BYIO) attracted particular attention due the expectation of a Jeff = 0 state for Ir5+ ions under jj-coupling scheme. However, controversies surround actual realization this state, as finite moments are consistently observed experimentally. We present multi-physics study system by progressively introducing nonmagnetic Sb5+ place (Ba2YIr1-ySbyO6, BYISO)....
We present an experimental investigation of the magnetic ground state in Ba$_4$NbIr$_3$O$_{12}$, a fractional valent trimer iridate. X-ray absorption and photoemission spectroscopy show that Ir valence lies between 3+ 4+ while Nb is pentavalent. Combined dc/ac magnetization, specific heat, muon spin rotation/relaxation ($\mu$SR) measurements reveal no phase transition down to 0.05~K. Despite significant Weiss temperature ($\Theta_{\mathrm{W}} \sim -15$ $-25$~K) indicating antiferromagnetic...
Comparative studies of structure, magnetism, and magnetoresistance (MR) have been carried out in A-site ordered NdBaMn2O6 (O-NB), disordered (D-NB) NdCaMn2O6 (D-NC). O-NB, where cations, Nd3+ Ba2+ (of different ionic sizes) are arranged periodically, undergoes structural transition with temperature, while no change is present D-NB cations randomly. However, transitions observed D-NC Ca2+ similar sizes. Magnetization (M) data shows O-NB has AFM ground state associated a lower structurally...
In the present work, we report a correlation between crystal structure, magnetic, and electrical properties in an exotic magnetic compound, NdBaMn2O6 having ~92% ordering Nd Ba, investigated using temperature-dependent synchrotron x-ray diffraction (XRD), dc magnetization transport measurements. Temperature-dependent XRD data reveals that compound undergoes various complex crystallographic phase transitions from high-temperature (T > 320 K) P4/mmm to intermediate (320 K – 280 Cmmm mixed...
The magnetic ground state in highly ordered double perovskites LaSr$_{1-x}$Ca$_x$NiReO$_6$ ($x$ = 0.0, 0.5, 1.0) were studied view of the Goodenough-Kanamori rules superexchange interactions. In LaSrNiReO$_6$, Ni and Re sublattices are found to exhibit curious states, but do not show any long range ordering. transition at $\sim$ 255 K is identified with sublattic sublattice interactions tuned by modifying Ni-O-Re bond angles via changing lattice structure through Ca doping. Upon doping,...
Effect of A -site cationic ordering on structural, transport and magnetic properties mixed-valent perovskite manganite NdBaMn 2 O 6 has been studied. Temperature ( T ) dependent x-ray diffraction data reveals that different types phase transitions seen in this compound explicitly depend the degree cations Nd 3+ Ba 2+ . For example, ordered undergoes multiple structural with decreasing , whereas disordered retains high crystal structure. Resistivity measurements show although both compounds...
Effect of A -site cationic ordering on structural, transport and magnetic properties mixed-valent perovskite manganite NdBaMn 2 O 6 has been studied. Temperature ( T ) dependent x-ray diffraction data reveals that different types phase transitions seen in this compound explicitly depend the degree cations Nd 3+ Ba 2+ . For example, ordered undergoes multiple structural with decreasing , whereas disordered retains high crystal structure. Resistivity measurements show although both compounds...