Article
Chemistry, Multidisciplinary
Shreya Kushwaha, Rajamani Nagarajan
Summary: In this study, Zn2MnO4 nano-material was successfully prepared by investigating the reaction between chloride salts of zinc and manganese with NaOH and recrystallizing under hydrothermal conditions. The characteristics and properties of the sample were confirmed through various analytical techniques, including its crystal structure, chemical composition, optical, and magnetic properties.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2021)
Article
Crystallography
Jonathan Gjerde, Mahmoud Hammouri, Radi A. Jishi
Summary: Perovskite oxide heterostructures offer new opportunities for advancements in technology and materials, particularly in the areas of magnetism and two-dimensional electron gases. This study focuses on a heterostructure composed of non-polar elements, EuO and EuTiO3, which exhibit conductivity due to oxygen vacancies. Additionally, the interface of this heterostructure is predicted to have spin-polarized free electrons, suggesting potential for future research and device applications.
Article
Instruments & Instrumentation
Haiming Huang, Mingming Shuai, Yulong Yang, Rui Song, Yanghui Liao, Lifeng Yin, Jian Shen
Summary: This paper presents a cryogen-free system with SP-STM and MExFM capabilities for investigating spin structures at the atomic scale. The specially designed vibration isolation system allows for extremely low noise levels.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Chemistry, Multidisciplinary
Xiaoye Chen, Ming Lin, Jian Feng Kong, Hui Ru Tan, Anthony K. C. Tan, Soong-Geun Je, Hang Khume Tan, Khoong Hong Khoo, Mi-Young Im, Anjan Soumyanarayanan
Summary: This study unveils the evolution of chiral spin texture characteristics on a tunable multilayer platform using electron and X-ray microscopies as well as numerical simulations. It establishes a comprehensive microscopic framework for investigating and tailoring chiral spin texture character in multilayer films.
Article
Astronomy & Astrophysics
Riad Suleiman, Vasiliy S. Morozov, Yaroslav S. Derbenev
Summary: We propose a new design of small storage rings that are highly specialized for low energy polarized electron beams. This design eliminates spin precession caused by the magnetic dipole moment at any energy, while allowing for the accumulation of spin precession induced by the fundamental physics of interest. The rings can be used for direct measurement of the electron's permanent electric dipole moment, as well as for searching for dark energy and ultra-light dark matter.
Article
Multidisciplinary Sciences
S. Furkan Ozturk, Dimitar D. Sasselov
Summary: The origins of biological homochirality on early Earth are still unknown, but this study proposes a hypothesis regarding this phenomenon. The authors suggest that shallow closed-basin lakes on early Earth, which are expected to contain significant sedimentary magnetite deposits, could have been a plausible prebiotic environment. They hypothesize that ultraviolet (200-300 nm) irradiation of magnetite deposits could generate hydrated spin-polarized electrons that induce enantioselective prebiotic chemistry, thereby facilitating the synthesis of life's building blocks.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Physical
Thomas P. P. Fay, David T. T. Limmer
Summary: In this paper, a physically motivated framework is proposed to describe spin-selective recombination processes in chiral systems. Spin-selective reaction operators for recombination reactions of donor-bridge-acceptor molecules are derived based on chirality and spin-orbit coupling. It is found that spin polarization selectivity only arises in hopping-mediated electron transfer. The framework presented here can be extended to describe spin-selective recombination processes in more complex systems.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Ali Baghizadeh, Pegah Mirzadeh Vaghefi, Xing Huang, Jerome Borme, Bernardo Almeida, Andrei N. Salak, Marc-Georg Willinger, Vitor B. Amaral, Joaquim M. Vieira
Summary: Multiferroic materials with coexistence of magnetic and ferroelectric orders are promising candidates for magnetoelectric devices. Understanding the underlying mechanisms and tailoring the properties to make them suitable for such devices is challenging. Research on epitaxial films of (Lu,Sc)FeO3 shows an increase in the Neel ordering temperature, highlighting the significant impact of lattice strain on thin film properties.
Article
Chemistry, Multidisciplinary
Michael C. Boucher, Corinne E. Isaac, Peter Sun, Peter P. Borbat, John A. Marohn
Summary: The sensitivity of MRFM is limited by surface noise, but coating a thin-film polymer sample with metal can significantly reduce sample-related noise. In this study, a 12 nm gold layer was evaporated on a 40 nm nitroxide-doped polystyrene film, resulting in the inactivation of nitroxide spin labels to a depth of 20 nm. A laminated sample protocol was introduced, and a 20-fold increase in spin signal was observed using MRFM with a high-compliance cantilever. The observed signal is smaller than expected, and potential sources of loss are discussed.
Article
Materials Science, Multidisciplinary
Humaira Zafar, Shaima H. Albedwawi, Kyriaki Polychronopoulou, Dalaver Hussain Anjum
Summary: Lanthanide based high entropy oxide (HEO) catalyst supports show promise for catalysis reactions due to the interplay of structural, elemental, and chemical forces. However, determining the structure and chemistry of the phase is challenging because of the high number of elements involved. Researchers use various modalities of transmission electron microscopy (TEM) technique to determine both structure and oxidation states of the HEO phase in samples synthesized with the coprecipitation of five lanthanide metals.
Article
Chemistry, Multidisciplinary
Junxiong Hu, Yulei Han, Xiao Chi, Ganesh Ji Omar, Mohammed Mohammed Esmail Al Ezzi, Jian Gou, Xiaojiang Yu, Rusydi Andrivo, Kenji Watanabe, Takashi Taniguchi, Andrew Thye Shen Wee, Zhenhua Qiao, A. Ariando
Summary: This work demonstrates the emergence of robust spin-polarization in graphene on a ferrimagnetic insulating oxide Tm3Fe5O12 (TmIG) with large spin-splitting energy of up to hundreds of meV. Moreover, the induced spin-splitting energy can be tuned over a broad range by field cooling technique. The observed spin polarization in graphene with large and tunable spin-splitting energy promises the field of 2D spintronics.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Paul Moellers, Jimeng Wei, Soma Salamon, Manfred Bartsch, Heiko Wende, David H. Waldeck, Helmut Zacharias
Summary: The chirality-induced spin selectivity (CISS) effect allows for controlling spin-dependent chemical reactions, such as photoinduced water splitting. This effect has been observed in organic chiral molecules, but its emergence in chiral inorganic materials is still not well-understood. In this study, chiral CuO films were deposited on partially UV-transparent gold substrates and subjected to deep-UV laser pulses. The spin polarization of photoelectrons was measured and found to be energy dependent, suggesting a contribution from the CISS effect in addition to intrinsic spin polarization in the CuO film.
Article
Physics, Multidisciplinary
V. S. Rusetsky, V. A. Golyashov, S. V. Eremeev, D. A. Kustov, I. P. Rusinov, T. S. Shamirzaev, A. V. Mironov, A. Yu. Demin, O. E. Tereshchenko
Summary: New spin-dependent photoemission properties of alkali antimonide semiconductor cathodes are predicted based on optical spin orientation effect and DFT band structure calculations. A Na2KSb/Cs3Sb heterostructure is designed as a spin-polarized electron source, combined with an Al0.11Ga0.89As target as a spin detector with spatial resolution. The photoluminescence polarization and high polarization of the photoemitted electrons confirm the spin-dependent photoemission properties of the Na2KSb/Cs3Sb photocathode. It is found that the multi-alkali photocathode can provide highly collimated electron beams close to the electron thermal energy limit. Vacuum tablet-type sources of spin-polarized electrons are proposed for accelerators, eliminating the need for photocathode growth chambers in photoinjectors.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Jonathan Chuah, Anjam Khursheed
Summary: This paper introduces a design of a REELS attachment for LVSEM applications, which is achieved through ray paths simulation, aiming to achieve nanoscale spatial resolution in SEM. The design uses a retarding field electrostatic toroidal sector energy analyzer to lower kinetic energies of electrons for better energy resolution.
Article
Materials Science, Multidisciplinary
Jayanta Das
Summary: Surface antiferromagnetism of NiO film on Ag(001) is investigated using X-ray absorption and electron diffraction techniques. The study reveals a preferential stabilisation of magnetic domains with the magnetic axes parallel to the interface. Comparison of two imaging techniques shows that the in-plane component of the magnetic easy axes in complementary T-domains are parallel to each other.
Article
Chemistry, Physical
Thilini K. Ekanayaka, Hannah Kurz, Kayleigh A. McElveen, Guanhua Hao, Esha Mishra, Alpha T. N'Diaye, Rebecca Y. Lai, Birgit Weber, Peter A. Dowben
Summary: The spin state transition behavior of Fe(ii) spin crossover coordination polymer crystallites at the surface differs from the bulk, possibly due to factors such as oxidation, differences in surface packing, and changes in coordination. Some Fe(ii) spin crossover coordination polymers may be photoactive enough to prevent discernment of the spin state transition using X-ray spectroscopies.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Shenli Zhang, I-Ting Chiu, Min-Han Lee, Brandon Gunn, Mingzhen Feng, Tae Joon Park, Padraic Shafer, Alpha T. N'Diaye, Fanny Rodolakis, Shriram Ramanathan, Alex Frano, Ivan K. Schuller, Yayoi Takamura, Giulia Galli
Summary: The oxygen vacancy concentration in cobaltites can be determined by the change in O K-edge XA spectra peak positions. The variation of Co-O bond length and Co-O-Co bond angle is also correlated with the presence of oxygen vacancies. The resistivity of the oxide material can be modified by adjusting the defect concentration, without any structural transformation.
CHEMISTRY OF MATERIALS
(2022)
Article
Physics, Condensed Matter
Guanhua Hao, Ashley S. Dale, Alpha T. N'Diaye, Rajesh Chopdekar, Roland J. Koch, Xuanyuan Jiang, Corbyn Mellinger, Jian Zhang, Ruihua Cheng, Xiaoshan Xu, Peter A. Dowben
Summary: Compact domain features were observed in spin crossover [Fe{H2B(pz)(2)}(2)(bipy)] molecular thin film systems. Monte Carlo simulations support the presence of intermolecular interactions that can be described by a two-dimensional Ising model. These interactions contribute to the formation of largely high spin state domain structure.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Materials Science, Ceramics
Aida Serrano, Eduardo Garcia-Martin, Cecilia Granados-Miralles, Jesus Lopez-Sanchez, Giulio Gorni, Adrian Quesada, Jose F. Fernandez
Summary: This study investigated the influence of different organic solvents on SrF12O19 platelet-based permanent magnets during the cold sintering process, revealing that the choice of solvent affects magnetic response, morphology, and structural properties. Additionally, post-annealing was found to improve the mechanical integrity and magnetic properties of the ferrite magnets.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Chemistry, Applied
Marcos Lucero, Tucker M. Holstun, Yudong Yao, Ryan Faase, Maoyu Wang, Alpha T. N'Diaye, David P. Cann, Joe Baio, Junjing Deng, Zhenxing Feng
Summary: This study demonstrates a novel dual-shell coating system on LiCoO2 electrode particles using a facile and scalable sol-gel technique. The coating system composed of Li2SrSiO4 and Al2O3 exhibits superior cycling stability and specific capacity.
JOURNAL OF ENERGY CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Grace A. Pan, Qi Song, Dan Ferenc Segedin, Myung-Chul Jung, Hesham El-Sherif, Erin E. Fleck, Berit H. Goodge, Spencer Doyle, Denisse Cordova Carrizales, Alpha T. N'Diaye, Padraic Shafer, Hanjong Paik, Lena F. Kourkoutis, Ismail El Baggari, Antia S. Botana, Charles M. Brooks, Julia A. Mundy
Summary: Epitaxial stabilization of rare-earth nickelates in the Ruddlesden-Popper form Ndn+1NinO3+1 has been demonstrated using molecular beam epitaxy. The stoichiometry of the parent perovskite NdNiO3 can be optimized to reproducibly synthesize the n = 1 - 5 member compounds. X-ray absorption spectroscopy reveals systematic changes in nickel-oxygen hybridization and nominal nickel filling across the series from n = 1 to infinity.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Chemistry, Physical
Adolfo del Campo, Sandra Ruiz-Gomez, Eva M. Trapero, Cecilia Granados-Miralles, Adrian Quesada, Michael Foerster, Lucia Aballe, Jose Emilio Prieto, Juan de la Figuera
Summary: The study reveals distinct evolutions of the Verwey transition on magnetite islands of different thicknesses, with islands thicker than 20nm showing differences in charge order compared to their thinner counterparts.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Sandra Ruiz-Gomez, Anna Mandziak, Laura Martin-Garcia, Jose Emilio Prieto, Pilar Prieto, Carmen Munuera, Michael Foerster, Adrian Quesada, Lucia Aballe, Juan de la Figuera
Summary: This study conducted a detailed analysis of the structural, magnetic, and chemical properties of non-stoichiometric cobalt ferrite micrometric crystals. With the use of advanced techniques such as x-ray magnetic circular dichroism, photoemission microscopy, low-energy electron microscopy, and atomic force microscopy, the magnetization vector inside the crystals was resolved at the nanoscale, and the location of magnetic domain walls was correlated with different types of defects. The findings are crucial for understanding the magnetic properties of thin films and nanostructures.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Eduardo Garcia-Martin, Cecilia Granados-Miralles, Sandra Ruiz-Gomez, Lucas Perez, Adolfo del Campo, Jesus Carlos Guzman-Minguez, Cesar de Julian Fernandez, Adrian Quesada, Jose F. Fernandez, Aida Serrano
Summary: The use of rare-earth-based permanent magnets is crucial for technological development. This study introduces a cold sintering process (CSP) for sintering composite permanent magnets based on strontium ferrite (SFO). The results show that control of composition and grain size enables the production of attractive magnetic properties in the sintered magnets.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
G. D. Soria, A. Serrano, J. E. Prieto, A. Quesada, G. Gorni, J. de la Figuera, J. F. Marco
Summary: We investigated the influence of the annealing treatment on the crystalline growth of previously deposited SrFe12O19 films on Si (100) substrates by RF magnetron sputtering. The results showed that the as-grown film consisted of nanocrystalline maghemite nanoparticles and amorphous strontium oxide, while the annealed film exhibited a strontium hexaferrite canonical structure with a c-axis orientation. The findings were obtained through various analysis techniques, including Mossbauer spectroscopy, EXAFS, and XANES data.
JOURNAL OF MATERIALS RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Thilini K. Ekanayaka, Okten Ungor, Yuchen Hu, Esha Mishra, Jared P. Phillips, Ashley S. Dale, Saeed Yazdani, Ping Wang, Kayleigh A. McElveen, M. Zaid Zaz, Jian Zhang, Alpha T. N'Diaye, Christoph Klewe, Padraic Shafer, Rebecca Y. Lai, Robert Streubel, Ruihua Cheng, Michael Shatruk, Peter A. Dowben
Summary: Modifications driven by TCNQ affect the spin state configuration and electric conductivity of [Fe(3-bpp)2](TCNQ)2 and [Fe{H2B(pz)2}2(bipy)] and TCNQ mixtures. The addition of TCNQ increases the conductivity and carrier lifetimes of [Fe{H2B(pz)2}2(bipy)]. TCNQ also enhances the transistor carrier mobility of [Fe{H2B(pz)2}2(bipy)] thin films grown using DMF.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Esha Mishra, Thilini K. Ekanayaka, Theodoros Panagiotakopoulos, Duy Le, Talat S. Rahman, Ping Wang, Kayleigh A. McElveen, Jared P. Phillips, M. Zaid Zaz, Saeed Yazdani, Alpha T. N'Diaye, Rebecca Y. Lai, Robert Streubel, Ruihua Cheng, Michael Shatruk, Peter A. Dowben
Summary: This study investigates the influence of an interface between a semiconducting polyaniline polymer or a polar poly-D-lysine molecular film and valence tautomeric complexes on the electronic structure. X-ray photoemission, X-ray absorption, inverse photoemission, and optical absorption spectroscopy measurements, guided by density functional theory, were used to identify electronic transitions and orbitals. The choice of substrate had little effect on the electronic structure, except for slight modifications in binding energies and orbital levels. A significant ligand-to-metal charge transfer state was observed in the Co-II high-spin state, which was insensitive to the interface between the polymer and tautomeric complexes.
Article
Chemistry, Physical
Thilini Ekanayaka, Tao Jiang, Emilie Delahaye, Olivier Perez, Jean-Pascal Sutter, Duy Le, Alpha T. N'Diaye, Robert Streubel, Talat S. Rahman, Peter A. Dowben
Summary: A chiral 3D coordination compound, [Gd-2(L)(2)(ox)(2)(H2O)(2)], arranged around a dinuclear Gd unit, has been characterized by X-ray photoemission and X-ray absorption measurements. The Gd 5p core level photoemission spectra indicate the dominance of spin orbit coupling over j-J coupling observed in the Gd metal spectra, suggesting the absence of inversion symmetry due to the ligand field. Density functional theory calculations predict antiferromagnetic alignment of the Gd-2 dimers and a band gap consistent with optical absorption.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Coatings & Films
Heshan Yu, Tieren Gao, A. T. N'Diaye, E. Arenholz, Suchismita Sarker, Apurva Mehta, Xiaohang Zhang, Ichiro Takeuchi
Summary: We have fabricated high-quality polycrystalline Fe1-xRhx composition-spread thin films and investigated their structural and magnetic transformations. The Fe1-xRhx film undergoes a phase transition from α to γ phase, accompanied by a magnetic transition from ferromagnetic to paramagnetic phase, as the Rh concentration increases. We constructed a thin-film phase diagram of Fe1-xRhx based on the structural and magnetic properties, which showed slightly different transition behaviors compared to bulk alloys.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Chemistry, Multidisciplinary
Jesus Carlos Guzman-Minguez, Cecilia Granados-Miralles, Patrick Kuntschke, Cesar de Julian Fernandez, Sergey Erokhin, Dmitry Berkov, Thomas Schliesch, Jose Francisco Fernandez, Adrian Quesada
Summary: This study aims to explore the magnetic properties of hard-soft composite permanent magnets and their correlation with microstructure. The experimental results show that increasing the particle size of the soft phase can enhance the remanence in injection molded magnets. Through experimental analysis and simulations, it is revealed that the interaction between the hard and soft phases is of a dipolar nature.
Article
Microscopy
C. Gao, C. Hofer, T. J. Pennycook
Summary: Ptychography provides high dose efficiency images that can reveal light elements next to heavy atoms. However, contrast reversals can occur when the projected potential becomes strong. Recent research has shown that these reversals can be counteracted by adapting the focus. This study explains why the best contrast is often found with the probe focused to the middle of the sample and highlights the importance of convergence angle in thin samples to remove contrast reversals.
Article
Microscopy
J. Lindner, U. Ross, T. Meyer, V. Boureau, M. Seibt, Ch. Jooss
Summary: Phase-shifting electron holography is an excellent method with high phase sensitivity to reveal electron wave phase information. An advanced drift correction scheme is proposed in this study, which exploits the interface of the TEM specimen and the vacuum area in the hologram. This method allows for obtaining reliable phase information.
Article
Microscopy
Ali Jaberi, Nicolas Brodusch, Jun Song, Raynald Gauvin
Summary: This study investigates knock-on damage in lithium-ion batteries (LIBs) by computing threshold displacement energies (TDEs) and performing Monte Carlo simulation. The results indicate that Li is most sensitive to knock-on damage at moderate electron energies, and TDE is the principal parameter for assessing Li sensitivity to knock-on damage across similar structures.
Article
Microscopy
Alexander Schroeder, Christopher Rathje, Leon van Velzen, Maurits Kelder, Sascha Schaefer
Summary: This study utilizes novel event-based electron detector platforms to extend the temporal resolution of electron microscopy. By training a neural network to predict electron arrival time, the researchers were able to improve the timing accuracy and achieve a promising solution for enhancing electron timing precision in various electron microscopy applications.
Article
Microscopy
Avi Auslender, Nivedita Pandey, Amit Kohn, Oswaldo Dieguez
Summary: This article describes a faster implementation based on DFT for computing the mean inner potential of crystals, providing quantum-mechanical calculations beyond the independent-atom approximation. The study also reveals the dependence of the mean inner potential on sample boundary conditions, mass density, and magnetic susceptibility, highlighting its correlation with various material properties.
Article
Microscopy
Zhidong Yang, Dawei Zang, Hongjia Li, Zhao Zhang, Fa Zhang, Renmin Han
Summary: In this work, we propose a self-supervised deep learning model for cryo-ET volumetric image denoising based on noise modeling and sparsity guidance. Experimental results demonstrate that our method can achieve reliable denoising by training on single noisy volume and outperform existing methods.
Article
Microscopy
J. Kuttruff, J. Holder, Y. Meng, P. Baum
Summary: In this study, a robust clustering algorithm is proposed that can find clusters in a continuous stream of raw data in real time. This algorithm converts pixel hits measured by hybrid pixel detectors to real single-electron events. By continuously comparing with previous hits, the algorithm efficiently identifies the merging of new and old events.
Article
Microscopy
D. G. Senturk, C. P. Yu, A. De Backer, S. Van Aert
Summary: This article presents a statistics-based method for accurately counting the number of atoms in nanostructures, especially for images acquired with low electron doses and multiple element structures.
Article
Microscopy
Mauricio J. Prieto, Lucas de Souza Caldas, Liviu C. Tanase, Thomas Schmidt, Oscar Rodriguez de la Fuente
Summary: This study presents a synchrotron-based investigation of the synthesis process of a magnetite/hematite bilayer. Ion bombardment gradually transforms hematite into magnetite, and the growth of magnetite leads to the formation of stable boundaries. These findings are significant for understanding novel oxide heterostructures.
Article
Microscopy
Emre Yoruk, Holger Klein, Stephanie Kodjikian
Summary: Beam sensitive nanomaterials pose challenges for crystallographic structure determination. A dose symmetric electron diffraction tomography (DS-EDT) method is developed to reduce beam damage and obtain complete data sets by merging individual datasets from multiple crystals.
Article
Microscopy
A. Pofelski, Y. Zhu, G. A. Botton
Summary: The precision and sensitivity of the GPA method for strain characterization is a widely discussed topic. This study introduces the concept of phase noise and analyzes the parameter of sampling to improve the precision of GPA. Experimental and theoretical results demonstrate that using a larger pixel spacing in STEM can enhance the precision and sensitivity of the GPA method.
Article
Microscopy
Sangjun Kang, Di Wang, Christian Kuebel, Xiaoke Mu
Summary: Transmission electron microscopy is a valuable tool for assessing strain fields within materials. However, using thin specimens in TEM analysis can affect atomic configuration and deformation structure.
