Article
Chemistry, Physical
Usman Khan, Adeela Nairan, Xusheng Wang, Karim Khan, Ayesha Khan Tareen, Dang Wu, Junkuo Gao
Summary: Mixed transition metals and their oxides have attracted significant research attention due to their wide range of applications in electronics, magnetism, and electrochemical energy storage and conversion devices. In this study, CoMn2O4 spinel oxide was synthesized through the auto-combustion method, with the structure and phase purity confirmed by X-ray diffraction. The oxide and hydroxyl groups were identified as the major active sites through Fourier transform infrared spectroscopy. The synthesized sample exhibited near-infrared light activity with a bandgap of 1.3 eV, as determined by UV-Vis spectroscopy. The average particle size of CoMn2O4 was found to be 161 +/- 26 nm through scanning electron microscopy. X-ray photoelectron spectra showed a mixed spinel structure containing Co and Mn cations. Magnetic investigations revealed a ferrimagnetic response in CoMn2O4 and the emergence of a large exchange bias above the transition temperature due to the presence of Griffiths phase.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Pragya Gupta, D. Pal
Summary: We systematically studied the structural and magnetic properties of Nd1-xPrxCrO3 (0.0 <= x <= 0.30) perovskites. The XPS measurements confirmed the desired Pr (3+) valence state for the samples. We observed an increase in magnetization and antiferromagnetic ordering temperature (T-N), as well as a decrease in spin-reorientation transition temperature (T-SR) with Pr substitution. The changes in the Cr-O bond length affected the exchange bias field and magnetization. This study sheds light on the spin-reorientation, exchange bias effect, and structural features in Nd1-xPrxCrO3 compounds.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
M. Slezak, H. Nayyef, P. Drozdz, W. Janus, A. Koziol-Rachwal, M. Szpytma, M. Zajac, T. O. Mentes, F. Genuzio, A. Locatelli, T. Slezak
Summary: The magnetic properties of easy-plane antiferromagnetic NiO(111) thin films epitaxially grown on ferromagnetic Fe(110) layers can be modified by tuning the thickness of Fe, changing the temperature, or applying small external magnetic field. The orientation and anisotropy of the NiO spins are determined by the underlying ferromagnetic Fe layer.
Article
Chemistry, Physical
Xiaoxuan Ma, Wencheng Fan, Gang Zhao, Haiyang Chen, Chuankun Wang, Baojuan Kang, Zhenjie Feng, Jun-Yi Ge, Wei Ren, Shixun Cao
Summary: The magnetic behavior of a rare-earth orthoferrite ErFeO3 single crystal can be controlled by low magnetic fields, with two types of spin switching observed below the spin reorientation transition temperature. The applied magnetic fields can regulate the spin switching along the a-axis of the single crystal, while understanding the magnetic reversal effects can help explore potential applications in information devices.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Physics, Condensed Matter
Pragya Gupta, D. Pal
Summary: The evolution of coupled phonons and exchange bias in perovskite-type Nd1-xEuxCrO3 samples was studied through temperature-dependent Raman spectroscopy and dc magnetization measurements. Non-monotonic behavior of the EB field around T* was observed, with T* lying between T-N and T-SR, confirming strong spin-phonon coupling through temperature dependence of phonon modes. The additional anomaly observed in low-temperature spin-phonon behavior was imprinted in T* from the non-monotonicity of the EB.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Physics, Condensed Matter
Clemens Ritter, Rui Vilarinho, Joaquim Agostinho Moreira, Matus Mihalik, Marian Mihalik, Stanislav Savvin
Summary: We used high resolution and high intensity neutron powder diffraction to study the magnetic order and spin reorientation transition in orthoferrite DyFeO3. We found that at low temperatures, the Fe-sublattice shows a Gamma(1) type order while the Dy-sublattice exhibits an incommensurate magnetic structure. This is an important finding in DyFeO3, which has been overlooked in recent discussions on its multiferroic properties.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Applied
Lanping He, Cangmin Wang, Shaoting Wang, Wanyu Li, Yang Jiang, Weifeng Ge, Linlin An, Huaili Qiu, Meixia Chen, Yuanjun Yang, Lan Wang
Summary: This paper investigates the influence of in situ growth magnetic field on the electric-field control of magnetic anisotropy in Co40Fe40B20/(011)-Pb(Mg1/3Nb2/3)(0.7)Ti0.3O3 [CoFeB/(011)-PMN-PT] composite multiferroic heterostructures. The results show that the electric-field-controlled modulation ratios of magnetic coercivity H-C and saturation magnetic field H-S can be significantly enhanced in the H-g2 mode compared to the H-g1 mode. The study reveals a new approach for the design of spintronic devices based on multiferroic heterostructures.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Multidisciplinary Sciences
Nandita Deb, Rimi Rashid, H. Das, Ishtiaque M. Syed, S. Manjura Hoque
Summary: In this study, nano-scale alpha-Fe2O3 particles were prepared using a hydrothermal technique and functionalized with chitosan. The results showed that the alpha-Fe2O3 nanoparticles had a single-phase structure with expected lattice constants and grain size. Additionally, the chitosan-coated particles exhibited a high zeta potential. Cell culture and hyperthermia experiments demonstrated that the nanohybrids had high maximum temperature and specific loss power within a certain concentration range.
ROYAL SOCIETY OPEN SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
O. V. Koplak, R. B. Morgunov
Summary: Magnetic anisotropy and interface exchange interaction were analyzed in α-Fe core microwire covered with PrDyCoFeB amorphous shell. The study revealed a potential application of the core/shell microwires in magnetocaloric applications.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Dariusz Sztenkiel
Summary: We report on a new effect called spin orbital reorientation transition (SORT) that occurs at two magnetic fields, B-SORT1 and B-SORT2, in small Mn3+ magnetic clusters in wurtzite GaN. This effect is observed in magnetization curves calculated using the crystal field model approach and suggests a reversal in the computed magnetic anisotropy on increasing B across B-SORT. The SORT effect is explained by the interplay of the crystalline environment and spin-orbit coupling.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Chemistry, Physical
Azam Ali Khan, Anju Ahlawat, Pratik Deshmukh, M. N. Singh, Archna Sagdeo, Vasant Sathe, A. K. Karnal, S. Satapathy
Summary: This study investigates the magneto-structural properties of TmFeO3 and Sm-substituted TmFeO3, showing a significant impact of Sm substitution on magnetic anisotropy and spin reorientation transition temperature. A sudden decrease in coercivity was observed in the SRT region, and anomalous behavior in lattice parameters near SRT confirmed the system's spontaneous magnetostriction. Raman spectroscopy revealed a strong anomaly in phonon frequency around SRT, indicating spin-lattice coupling in the nanoparticles.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Zhiqiang Sun, Huan Song, Shuang Zhu, Xiaoxuan Ma, Wanting Yang, Chenfei Shi, Baojuan Kang, Rongrong Jia, Jin-Ke Bao, Shixun Cao
Summary: We have prepared single crystal Nd0.8Pr0.2FeO3 and investigated the effect of Pr-doping on its magnetic properties. The Pr-doping lowered the spin reorientation transition temperature range and exhibited excellent properties in spin switching. Different types of spin switching events were observed in Nd0.8Pr0.2FeO3, and a significant magnetic entropy change was observed at low temperatures and high magnetic fields.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Zhiqiang Sun, Huan Song, Shuang Zhu, Xiaoxuan Ma, Wanting Yang, Chenfei Shi, Baojuan Kang, Rongrong Jia, Jin-Ke Bao, Shixun Cao
Summary: Single crystal Nd0.8Pr0.2FeO3 was prepared using the optical floating zone method, and the effect of Pr-doping on its magnetic properties was investigated. 20% Pr3+ doping exhibited superior spin switching performance at lower temperatures. These results provide a better understanding of the doped magnetic anisotropy in RFeO3 and offer new possibilities in the application of magnetic switching materials under low magnetic fields.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Physics, Multidisciplinary
Dapeng Zhu, Tianrui Zhang, Xiao Fu, Runrun Hao, Amir Hamzic, Huaiwen Yang, Xueying Zhang, Hui Zhang, Ao Du, Danrong Xiong, Kewen Shi, Shishen Yan, Shufeng Zhang, Albert Fert, Weisheng Zhao
Summary: Recent studies have shown that antiferromagnetic insulators efficiently support spin current. In this study, we observe a strong temperature dependence and reversed sign of dampinglike spin-orbit torque (SOT) in Pt/NiO/CoFeB, which is different from the slight variation with temperature observed in Pt/CoFeB bilayer. The negative dampinglike SOT at low temperatures is proposed to be mediated by magnetic interactions tied to the "exchange bias" in Pt/NiO/CoFeB, in contrast to the thermal-magnon-mediated scenario at high temperatures. These results highlight the potential to control SOT by tuning the magnetic structure in multilayers.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
J. Okamoto, A. Chainani, Z. Y. Chen, H. Y. Huang, A. Singh, T. Sasagawa, D. I. Khomskii, A. Fujimori, C. T. Chen, D. J. Huang
Summary: In this study, x-ray spectral evidence is presented for the evolution of valence- and spin-specific tetragonal distortions in single-layer cobaltates. The measurements reveal changes in tetragonal splitting of high-spin Co2+ and low-spin Co3+ states as Sr-doping increases, shedding light on the origin of magnetic anisotropy and in-plane resistivity changes in mixed-valence cobaltates.
Article
Chemistry, Multidisciplinary
Sohel Akhtar, Sukhen Bala, Avik De, Krishna Sundar Das, Amit Adhikary, Shubhra Jyotsna, Pankaj Poddar, Raju Mondal
CRYSTAL GROWTH & DESIGN
(2019)
Review
Chemistry, Multidisciplinary
Puneet Khandelwal, Dheeraj K. Singh, Pankaj Poddar
Article
Chemistry, Multidisciplinary
Monika Ghalawat, Pankaj Poddar
Article
Chemistry, Physical
Monika Ghalawat, Pankaj Poddar
Summary: Despite significant progress in understanding the nucleation and growth processes of Fe3Se4 nanoparticles, controlling their size and shape remains challenging. This study aims to investigate and control the influence of various reaction pathways on the morphology and size of Fe3Se4 nanocrystals.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Materials Science, Multidisciplinary
Shubhra Jyotsna, Subha Sadhu, Vinay Sharma, Preeti Gupta, Geeta Sharma, Pankaj Poddar
Summary: Green luminescent graphene quantum dots obtained from combustion of white printing paper were used for detection of metal ions and explosives in water. A sensitive sensing system was developed to detect metal ions and explosives in the environment.
MRS COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Monika Ghalawat, Pankaj Poddar
Summary: For the first time, this study presents the correlation between phase structure and magnetic properties in the Fe-Se system. By synthesizing FexSey compounds with different Fe/Se ratios, significant variations in magnetic properties were observed. Among the four studied phases, Fe3Se4 and Fe7Se8 showed ferrimagnetic and semihard magnetic properties, while FeSe2 and β-FeSe exhibited weaker magnetism and were prone to surface oxidation.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Spectroscopy
Supriya Ughade, Pankaj Poddar
Summary: Rare earth chromates (RCrO4) undergo a structural phase transition from monazite to zircon-type due to the decrease in rare-earth ion size, and they also exhibit an intermediate mixed phase. However, there has been no systematic study on the influence of structural distortion on their phononic behavior, which is sensitive to environmental variations.
JOURNAL OF RAMAN SPECTROSCOPY
(2023)
Article
Chemistry, Multidisciplinary
Dinesh Singh, Bhavana Joshi, Pankaj Poddar
Summary: The thickness and exposed crystalline facets have a crucial impact on the oxygen evolution reaction (OER) of 2D ferroelectric nanosheets. Iron-substituted BiOCl nanosheets with larger thickness and exposed (001) facet exhibit higher ferroelectric polarization, leading to superior electrocatalytic activity and remarkable stability.
Article
Chemistry, Multidisciplinary
Dinesh Singh, Pankaj Poddar
Summary: Thiol-capped metal nanoparticles were synthesized using bismuth dodecanethiolate as a precursor, with sodium borohydride as the reducing agent. These crystalline nanoparticles exhibited efficient catalytic activity in reducing 4-nitrophenol to 4-aminophenol within 12 minutes, and remained catalytically active for up to three cycles.
Article
Materials Science, Multidisciplinary
Shubhra Jyotsna, Pankaj Poddar
Summary: The magnetic properties of trigonal 3C Fe7S8 nanoparticles synthesized by thermal decomposition method were investigated. The results show magnetic ordering with high Curie transition temperature (T-C > 300 K) in the specimen. The compound exhibits ferrimagnetic ordering in the temperature range of 7 to 300 K, with increased coercivity (H-C), saturation magnetization (M-60 kOe), and remanent magnetization (M-R) at lower measuring temperatures. The maximum energy product (BHmax) reaches the highest value of 128 kG Oe at 7 K.
BULLETIN OF MATERIALS SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Mousumi Sen Bishwas, Monika Malik, Pankaj Poddar
Summary: This work describes the sensitive, rapid and reversible detection of explosive molecules in the vapor phase using metal-organic frameworks as adsorbents and Raman spectroscopy as the detection method. The interaction between the MOF and nitro analytes plays a crucial role in the detection process, demonstrating the potential for developing handheld explosive detectors.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
S. Irudhaya Raj, Adhish Jaiswal, Imran Uddin
Article
Chemistry, Multidisciplinary
Monika Malik, Preeti Padhye, Pankaj Poddar
Article
Chemistry, Multidisciplinary
Puneet Khandelwal, Aftab Alam, Arpankumar Choksi, Samit Chattopadhyay, Pankaj Poddar
Article
Chemistry, Multidisciplinary
Monika Malik, Preeti Padhye, Pankaj Poddar