Article
Physics, Multidisciplinary
Jean-Come Philippe, Alexis Lespinas, Jimmy Faria, Anne Forget, Dorothee Colson, Sarah Houver, Maximilien Cazayous, Alain Sacuto, Indranil Paul, Yann Gallais
Summary: Anisotropic strain selectively affects the role of nematic fluctuations in promoting superconductivity. Our results confirm the significance of nematic fluctuations in electron pairing.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Jaafar N. Ansari, Karen L. Sauer, Igor I. Mazin
Summary: In this study, the effect of Co doping on the real-space nematic fluctuations in BaFe2As2 is investigated by combining nuclear magnetic resonance data with first-principles calculations. It is found that the dynamics of nematic fluctuations are exceptionally slow even in the formally tetragonal phase.
Article
Physics, Multidisciplinary
Haruyasu Sato, Mitsuhiro Akatsu, Ryosuke Kurihara, Yoshiaki Kobayashi, Yuichi Nemoto
Summary: The critical properties originating from degenerate orbitals at the ferro-quadrupole quantum critical point (QCP) in the iron pnictide superconductor Ba(Fe1-xCox)2As2 were investigated through ultrasonic experiments. The temperature dependence of various parameters, such as the elastic soft mode C66, Jahn-Teller energy Delta Q, Weiss temperature Theta Q, and hexadecapole susceptibility ultrasonic attenuation coefficient alpha 66, near the QCP were found to exhibit significant changes. The unconventional critical exponent z nu was observed to be 3 near the QCP, suggesting enhanced quantum fluctuations. These observations indicate the potential key role of order parameter fluctuations in the superconductivity.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Materials Science, Multidisciplinary
Qiang Zou, Mingming Fu, Zhiming Wu, Li Li, David S. Parker, Athena S. Sefat, Zheng Gai
Summary: Electronic inhomogeneities in Co, Ni, and Cr doped BaFe2As2 single crystals were compared in different bulk property regions. Machine learning was used to categorize the inhomogeneous electronic states, revealing different origins and roles. While the relative percentages of electronic states varied in different samples, the total volume fractions were similar.
NPJ QUANTUM MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
M. H. Tang, C. H. Dong, Z. T. Xu, C. Liu, P. Yang, C. Tu, W. W. Guo, Y. C. Zhu, C. Yao, H. Huang, D. L. Wang, X. P. Zhang, Y. W. Ma
Summary: In this paper, a comparative investigation on the differences of vortex dynamics in Ba(Fe0.94Co0.06)2As2 single crystal, grain oriented polycrystal, and random oriented powder is conducted. It is found that the introduction of strong pins in the polycrystal effectively reduces the magnetization relaxation rates in the low magnetic field regime.
MATERIALS TODAY PHYSICS
(2022)
Article
Chemistry, Physical
Minu Kim, Graham M. McNally, Hun-Ho Kim, Mohamed Oudah, Alexandra S. Gibbs, Pascal Manuel, Robert J. Green, Ronny Sutarto, Tomohiro Takayama, Alexander Yaresko, Ulrich Wedig, Masahiko Isobe, Reinhard K. Kremer, D. A. Bonn, Bernhard Keimer, Hidenori Takagi
Summary: Superconductivity is observed in (Ba,K)SbO3, stabilized by high-pressure synthesis, with a positive oxygen-metal charge transfer energy. This discovery suggests that strong oxygen-metal covalency might be more important than the sign of the charge transfer energy in the origin of superconductivity in main-group perovskite superconductors.
Article
Engineering, Electrical & Electronic
Shoya Sakamoto, Guoqiang Zhao, Goro Shibata, Zheng Deng, Kan Zhao, Xiancheng Wang, Yosuke Nonaka, Keisuke Ikeda, Zhendong Chi, Yuxuan Wan, Masahiro Suzuki, Tsuneharu Koide, Arata Tanaka, Sadamichi Maekawa, Yasutomo J. Uemura, Changqing Jin, Atsushi Fujimori
Summary: The study investigates the perpendicular magnetic anisotropy of a layered ferromagnetic semiconductor using angle-dependent X-ray magnetic circular dichroism measurements. The large magnetic anisotropy is attributed to the anisotropic distribution of Mn 3d electrons and the lifting of degeneracy of p-d(xz), d(yz) hybridized states.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Physics, Applied
Rajyavardhan Ray, A. K. Himanshu, Golak K. Mandal, Uday Kumar, S. N. Jha, N. Patra, D. Bhattacharya, A. B. Shinde, Manuel Richter, P. S. R. Krishna
Summary: The study resolved the discrepancies over the structural details of Ba(Fe1/2Nb1/2)O-3 ceramics through X-ray diffraction and neutron powder diffraction measurements, revealing a cubic structure. An appropriate value of U for DFT+U calculations was obtained through comparison with X-ray absorption spectroscopy.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Ceramics
Dmitriy Fedulov, Vladislav Kozlov, Alexander Bush, Mikhail Talanov
Summary: In this work, Pb(Fe1-xCox)2/3W1/3O3 (PFCW) and Pb(Co1-yFey)1/2W1/2O3 (PCFW) ceramics were successfully fabricated by a solid-state reaction process. The formation of two different series of solid solutions with perovskite structure and substitution limits of Fe for Co (in PFCW) and Co for Fe (in PCFW) were confirmed. The dielectric study of the PFCW ceramics showed a crossover from relaxor ferroelectric to ferroelectric at x = 0.10, while the PCFW ceramics exhibited phase transitions at 320 K and 256 K. The temperature dependencies of the thermally stimulated depolarization currents of PFCW and PCFW solid solutions were also studied and discussed.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Alexandre Mesquita, Elio Thizay Magnavita Oliveira, Hugo Bonette de Carvalho
Summary: Gadolinium-doped strontium titanate (Sr1-xGdxTiO3) is a perovskite structure material with interesting thermomechanical, termoelectrical, and electrochemical properties. X-ray absorption spectroscopy was used to analyze the local and electronic structure of Sr1-xGdxTiO3 samples, showing that increasing Gd content causes disorder and leads to a small displacement of Ti atoms. Changes in the XANES spectra at O K-edge for Sr1-xGdxTiO3 samples are influenced by the increase in Gd concentration.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Teklie Lissanu Tegegne, Gebregziabher Kahsay
Summary: This study investigated the mathematical expressions of temperature and angle dependence of magnetic fields and Ginzburg-Landau characteristics in iron-based superconductors. Phase diagrams were plotted based on experimental values, showing the relationship between various parameters with temperature and angle variations. The theoretical investigation was found to be consistent with the obtained experimental results.
JOURNAL OF MAGNETICS
(2021)
Article
Chemistry, Physical
Parasmani Manju, Parasmani Rajput, Ankush Vij, Anup Thakur
Summary: This study presents a detailed analysis of the local electronic structure of host and dopant atoms in doping-assisted lattice site engineering through combined experimental and simulated X-ray absorption near edge structure. The results reveal that at low doping concentration, Dy tends to substitute the less symmetric Sr2+ site, while with an increase in doping concentration, Dy starts substituting the relatively more symmetric Zn2+ lattice site. The study deciphers the effect of lattice site occupancy on the local electronic structure of host and dopant atoms.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
Kristina S. Zinchenko, Fernando Ardana-Lamas, Issaka Seidu, Simon P. Neville, Joscelyn van der Veen, Valentina Utrio Lanfaloni, Michael S. Schuurman, Hans Jakob Worner
Summary: In this study, the fastest electronic relaxation dynamics to date was observed using attosecond transient-absorption spectroscopy (ATAS) extended to the carbon K-edge. By selectively launching wave packets in the two lowest electronic states of C2H4+, the electronic relaxation process was visualized and multidimensional structural dynamics of the molecule were simultaneously observed. These results demonstrate the capability to resolve the fastest electronic and structural dynamics in a broad class of organic molecules, showing that electronic relaxation in organic chromophores can occur within less than a single vibrational period.
Article
Physics, Condensed Matter
Xiaobing Li, Cong Tao, Shengdong Nie, Xuan Ren, Haiqing Xu, Haosu Luo, Kwok Ho Lam, Xiaoming Jiang, Zhi Guo
Summary: In this study, a large-sized multiferroics Pb(Fe1/2Nb1/2)O-3 (PFN) single crystal was grown by Bridgeman method to investigate the giant dielectric response. The synchrotron radiation soft x-ray absorption spectrum revealed the valence states of Fe in PFN crystal. PFN exhibits semiconductor behaviors in thermal active electrical conductivity investigation. The frequency-dependent dielectric constants were measured to study the dielectric relaxation behaviors, with two relaxation processes found and discussed based on the universal relaxation law for a dipolar system.
PHYSICA B-CONDENSED MATTER
(2022)
Article
Chemistry, Physical
Veronica Celorrio, Andrew S. Leach, Haoliang Huang, Shusaku Hayama, Adam Freeman, David W. Inwood, David J. Fermin, Andrea E. Russell
Summary: The study utilized in situ X-ray absorption and emission spectroscopies to examine the role of Mn ions in determining the oxygen reduction activity of LaMnO3 and CaMnO3. Results showed differences in redox behavior and oxygen vacancies between the two materials at various applied potentials. The findings have implications for understanding pseudocapacitive response and material degradation processes.
Article
Nanoscience & Nanotechnology
Hang Chen, Shahidul Asif, Kapildeb Dolui, Yang Wang, Jeyson Tamara-Isaza, V. M. L. Durga Prasad Goli, Matthew Whalen, Xinhao Wang, Zhijie Chen, Huiqin Zhang, Kai Liu, Deep Jariwala, M. Benjamin Jungfleisch, Chitraleema Chakraborty, Andrew F. May, Michael A. McGuire, Branislav K. Nikolic, John Q. Xiao, Mark J. H. Ku
Summary: The study reports on exfoliated flakes of cobalt-substituted Fe5GeTe2 (CFGT) that exhibit magnetism above room temperature. Ferromagnetism at room temperature was observed in CFGT flakes as thin as 16 nm using quantum magnetic imaging. This expands the portfolio of thin room temperature 2D magnet flakes exfoliated from robust single crystals.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
J. -q. Yan, M. A. McGuire
Summary: This paper introduces a less well-known vapor transport technique called self-selecting vapor growth, and reports on the growth of transition-metal halides using this technique. The research shows that the self-selecting vapor transport technique can provide large single crystals of transition-metal halides, demonstrating its potential for providing high-quality single crystals of quantum materials.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jierui Liang, Shanchuan Liang, Ti Xie, Andrew F. May, Thomas Ersevim, Qinqin Wang, Hyobin Ahn, Changgu Lee, Xixiang Zhang, Jian-Ping Wang, Michael A. McGuire, Min Ouyang, Cheng Gong
Summary: Exchange bias in van der Waals (vdW) magnets is crucial for magnetoresistive logic and memory devices. We demonstrate a facile method to achieve strong exchange bias in Fe5GeTe2 through atomic layer deposition (ALD) of oxides. By depositing Al2O3, ZnO, and V2O5 on Fe5GeTe2, exchange biases of 300-1500 Oe were obtained at 130 K. We show that the duration of oxidant pulse in each ALD cycle and the oxidant used in the process play a key role in enhancing the exchange bias strength. Our work highlights the importance of ALD-enabled oxidization of Fe5GeTe2 and establishes ALD of oxides as a promising approach for creating giant exchange bias in vdW magnets.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Crystallography
Duncan H. H. Moseley, Craig A. A. Bridges, Luke L. L. Daemen, Qiang Zhang, Michael A. A. McGuire, Ercan Cakmak, Raphael P. Hermann
Summary: Antimony oxides are important for catalysis and flame-retardant applications. Although the lattice dynamics properties of alpha-Sb2O3 and beta-Sb2O3 have been extensively studied, their anharmonicity and low-temperature structural information have not been directly investigated. In this study, we report the powder neutron diffraction data and structural information of both phases, revealing a small region of zero thermal expansion in beta-Sb2O3 along the c axis and a deviation in atomic displacement parameters in alpha-Sb2O3. These findings provide valuable insights for further investigations.
Article
Materials Science, Multidisciplinary
Andrew F. May, Eleanor M. Clements, Heda Zhang, Raphael P. Hermann, Jiaqiang Yan, Michael A. McGuire
Summary: EuCuP and EuCuAs were studied to investigate their magnetic phase transitions and magnetoelastic coupling. EuCuP exhibited two closely spaced features in thermal expansion and specific heat capacity around the Curie temperature, possibly indicating a cascading magnetic transition or an electronic transition closely coupled to the magnetic ordering. Stronger zero-field magnetoelastic coupling was observed in EuCuP compared to EuCuAs, which was attributed to the dominant ferromagnetic interaction in EuCuP and antiferromagnetic order in EuCuAs. Anisotropic thermal expansion and strong ferromagnetic correlations were observed in EuCuAs above T-N. Both compounds showed similar electrical and thermoelectric transport behaviors, suggesting intrinsic defects and potential for achieving narrow-gap semiconducting or semimetallic behavior with defect tuning.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Michael A. McGuire, Heda Zhang, Andrew F. May, Satoshi Okamoto, Robert G. Moore, Xiaoping Wang, Clement Girod, Sean M. Thomas, Filip Ronning, Jiaqiang Yan
Summary: Alloying indium into SnBi2Te4 induces bulk superconductivity with critical temperatures up to 1.85 K and upper critical fields up to about 14 kOe. This is confirmed by electrical and thermal measurements, and the presence of a superconducting gap near 0.25 meV is suggested. The superconductivity is type-II and the existence of topological surface states has been verified. The analogy with MnBi2Te4 motivates further interest in this family of compounds, which have potential for the study of topological superconductivity.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Daniel Multer, Jia-Xin Yin, Md. Shafayat Hossain, Xian Yang, Brian C. Sales, Hu Miao, William R. Meier, Yu-Xiao Jiang, Yaofeng Xie, Pengcheng Dai, Jianpeng Liu, Hanbin Deng, Hechang Lei, Biao Lian, M. Zahid Hasan
Summary: Direct imaging and magnetic tuning of flat band localization in kagome materials is achieved through scanning tunneling microscopy and photoemission spectroscopy. This study provides crucial insights into the localization of flat band states.
COMMUNICATIONS MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Elena Salagre, Pilar Segovia, Miguel Aïngel Gonzalez-Barrio, Matteo Jugovac, Paolo Moras, Igor Pis, Federica Bondino, Justin Pearson, Richmond Shiwei Wang, Ichiro Takeuchi, Elliot J. Fuller, Alec A. Talin, Arantzazu Mascaraque, Enrique G. Michel
Summary: We have developed a novel delithiation process for thin film lithium cobalt oxide cathodes. By using ion sputtering and annealing cycles, we can achieve delithiation without chemical byproducts and electrolyte interaction. This method allows for the identification of the effects of lithium extraction and provides detailed information on the role of oxygen and cobalt atoms in charge compensation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Yanxue Zhang, Gianluca D'Olimpio, Federica Bondino, Silvia Nappini, Marian Cosmin Istrate, Raman Sankar, Corneliu Ghica, Luca Ottaviano, Junfeng Gao, Antonio Politano
Summary: The chemical reactivity of cadmium diarsenide (CdAs2) towards ambient gases (oxygen and water) and air was assessed using density functional theory and experiments. The surface of CdAs2 forms an oxide skin, but its thickness remains nanometric even after one year in air. Therefore, future quantum devices based on Kramers-Weyl fermions could be stable in air, as the native oxide layer formed on chiral quantum materials actually protects their bulk features.
APPLIED SURFACE SCIENCE
(2023)
Article
Physics, Multidisciplinary
Ling-Fang Lin, Yang Zhang, Gonzalo Alvarez, Michael A. McGuire, Andrew F. May, Adriana Moreo, Elbio Dagotto
Summary: The stability range of the ferromagnetic phase in iron oxychalcogenide chain system is studied under modifications in the crystal fields and electronic correlation strength, leading to the discovery of a rich emergence of phases including ferromagnetic and antiferromagnetic metallic states. The results demonstrate the capability of the interorbital hopping mechanism in stabilizing ferromagnetic insulators, providing insights for the design of new ferromagnetic insulator materials.
COMMUNICATIONS PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Maximilian Mellin, Zhili Liang, Hadar Sclar, Sandipan Maiti, Igor Pis, Silvia Nappini, Elena Magnano, Federica Bondino, Ilargi Napal, Robert Winkler, Rene Hausbrand, Jan P. Hofmann, Lambert Alff, Boris Markovsky, Doron Aurbach, Wolfram Jaegermann, Gennady Cherkashinin
Summary: The thermal treatment of Li-rich cathodes with SO2 and NH3 gases improves capacity retention, rate capability, and voltage hysteresis in Li-ion batteries.
MATERIALS ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
Alaa Mohammed Idris Bakhit, Khadiza Ali, Anna A. Makarova, Igor Pis, Federica Bondino, Roberto Sant, Saroj P. Dash, Rodrigo Castrillo-Bodero, Yuri Hasegawa, J. Enrique Ortega, Laura Fernandez, Frederik Schiller
Summary: This study investigates the structural, electronic, magnetic properties, and chemical stability of a reactive metal, Europium, intercalated between a hexagonal boron nitride (hBN) layer and a Pt substrate. It is found that the intercalation of Europium leads to the formation of a hBN-covered ferromagnetic EuPt2 surface alloy with divalent Eu2+ atoms at the interface. The system is exposed to ambient conditions, and partial conservation of the divalent signal is observed, indicating the stability of the Eu-Pt interface. By using a curved Pt substrate, the changes in the Eu valence state and the protection against ambient pressure at different substrate planes are explored. The formation of the interfacial EuPt2 surface alloy remains consistent, but the resistance of the protective hBN layer to ambient conditions is reduced, likely due to surface roughness and discontinuous hBN coating.
Article
Materials Science, Multidisciplinary
Cristian Soncini, Abhishek Kumar, Federica Bondino, Elena Magnano, Matija Stupar, Barbara Ressel, Giovanni De Ninno, Antonis Papadopoulos, Efthymis Serpetzoglou, Emmanuel Stratakis, Maddalena Pedio
Summary: In devices based on organic semiconductors, the aggregation and inter-molecular interactions significantly affect the photo-physical and dynamical carrier properties. Understanding the interplay between the molecular structure and material properties is crucial for designing devices with optimized performance. This study investigates how different molecular structural arrangements modulate the charge transfer dynamics in cobalt phthalocyanine thin films.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Physics, Multidisciplinary
K. M. Taddei, V. O. Garlea, A. M. Samarakoon, L. D. Sanjeewa, J. Xing, T. W. Heitmann, C. dela Cruz, A. S. Sefat, D. Parker
Summary: Researchers have identified a potential candidate material, KNiAsO4, that may exhibit a spin-liquid ground state based on the Kitaev spin Hamiltonian. Experimental measurements show evidence of magnetic order and a gapped spin-wave spectrum, suggesting the presence of a well-defined spin-liquid state.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Liurukara D. Sanjeewa, V. Ovidiu Garlea, Randy S. Fishman, Mahsa Foroughian, Li Yin, Jie Xing, David S. Parker, Tiffany Smith M. Pellizzeri, Athena S. Sefat, Joseph W. Kolis
Summary: In this study, the magnetic phase diagram of the compound CsCo2(MoO4)2(OH) was determined through magnetic and neutron scattering measurements. The magnetic properties of CsCo2(MoO4)2(OH) are strongly influenced by the crystal lattice and can be easily controlled by magnetic fields. The compound exhibits unique magnetic exchange interactions between two types of Co2+ ions. The magnetic structure is antiferromagnetic along the b-axis at TN = 5 K, with two successive metamagnetic transitions observed. The compound shows promising potential for studying new physics related to sawtooth chain magnetism. Rating: 6/10.
MATERIALS CHEMISTRY FRONTIERS
(2023)
