Article
Materials Science, Ceramics
Hamed Bakhshi, Rasoul Sarraf-Mamoory, Amin Yourdkhani, Shaochang Song, Yu-Chih Tseng, Yurij Mozharivskyj
Summary: The SrTiO3 perovskites doped with Sm3+, Dy3+, and Nb5+ were prepared using the solid state reaction route (SSR) and spark plasma sintering (SPS) process. The SPS process in dynamic vacuum resulted in the formation of Ti3+ and Nb4+ species, leading to increased electrical conductivity. Substituting Sr with Sm and Dy effectively reduced the lattice thermal conductivity and increased the electron mobility and electrical conductivity. The thermoelectric measurements showed that the sample with a chemical composition of Sr0.95Sm0.05Ti0.9Nb0.1O3 reached a high figure of merit (zT) value.
CERAMICS INTERNATIONAL
(2022)
Article
Engineering, Electrical & Electronic
Steven Herold, Joerg Acker
Summary: The study investigates the influence of local strains and the initial topography of slurry and diamond wire saw wafers on the acid etching mechanism. Tensile strained silicon is found up to 2.7 µm deep in the saw damage and acts as an etching mask.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Chemistry, Physical
Lorenzo Rizzato, Jonathan Cavazzani, Andrea Osti, Marco Scavini, Antonella Glisenti
Summary: This study investigates the use of SrTiO3-supported Cu nanoparticles as LSPR-mediated catalysts for CO2 reduction. The researchers successfully incorporated copper into the perovskite structure, forming nanostructures on the surface through reducing treatments. Catalytic tests demonstrated the effectiveness of LSPR in CO2 activation.
Article
Chemistry, Physical
Juan Xie, Penghui Bai, Chenjie Wang, Ning Chen, Weifeng Chen, Ming Duan, Hu Wang
Summary: This study investigates the effect of doping SrTiO3 with an extremely low concentration of NiP on the catalytic activity of water splitting under visible light irradiation. It is found that the transformation of oxygen species and the construction of reactive lattice oxygen play a crucial role in improving the hydrogen generation performance. Adjusting the ratio of different oxygen species is an effective strategy to fabricate high-performance photocatalysts for H-2 evolution.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Physics, Multidisciplinary
Kyosuke Ishito, Huiling Mao, Yusuke Kousaka, Yoshihiko Togawa, Satoshi Iwasaki, Tiantian Zhang, Shuichi Murakami, Jun-ichiro Kishine, Takuya Satoh
Summary: In this study, truly chiral phonons were identified in bulk crystals using circularly polarized Raman spectroscopy and first-principles calculations. The findings have significant implications for the development of opto-phononic-spintronic devices, enabling the transfer of pseudo-angular momentum from photons to electron spins through propagating chiral phonons.
Article
Physics, Applied
Gennadiy A. Komandin, Artem M. Kuzmenko, Igor E. Spektor, Alexander A. Mukhin
Summary: The absorption mechanisms in orthoferrite TbFeO3 were studied using various spectroscopy techniques. The spectra were analyzed using the oscillator model and four-parameter model, and the parameters were determined. The main absorption processes were identified, including contributions from phonons, multi-phonon processes, electron transitions, and antiferromagnetic resonance modes. The electrodynamic response in TbFeO3 showed significant absorption in the THz range due to multi-phonon processes, surpassing optical phonon contribution by an order of magnitude at room temperature.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Food Science & Technology
Setareh Shiroodi, Michael H. Schwarz, Nitin Nitin, Reza Ovissipour
Summary: This study evaluated the impact of nanobubbles and neutral electrolyzed water on different microbial biofilms, finding that nanobubbles alone or in combination with neutral electrolyzed water could effectively remove biofilms, reduce bacterial adhesion, and show potential as a new technology to enhance the efficacy of conventional sanitizers.
FOOD AND BIOPROCESS TECHNOLOGY
(2021)
Article
Chemistry, Physical
Ying-Zhong Ma, Benjamin Doughty
Summary: Nonlinear optical (NLO) microscopy relies on multiple light-matter interactions to provide unique contrast mechanisms and imaging capabilities. However, strong excitation fields often cause photobleaching and interruption in systems of interest. This perspective focuses on the limitations of two NLO imaging modalities and highlights the unique potential of quantum-light-enabled techniques.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Physics, Applied
Brian Douglas Rummel, Leonid Miroshnik, Marios Patriotis, Andrew Li, Talid R. Sinno, Michael David Henry, Ganesh Balakrishnan, Sang M. Han
Summary: Surface acoustic wave devices were fabricated on a GaAs (100) substrate to demonstrate the capability of 2D Raman microscopy as an imaging technique for acoustic waves on the surface of a piezoelectric substrate. An analytical model was derived to relate Raman peak broadening to the near-surface strain field of the GaAs surface produced by the surface acoustic waves, and atomic force microscopy was used to confirm the presence of a standing acoustic wave. Stress calculations for both imaging techniques were in good agreement, demonstrating the potential of this Raman analysis.
APPLIED PHYSICS LETTERS
(2021)
Review
Polymer Science
Julie L. P. Jessop
Summary: This article discusses the advantages of using Raman spectroscopy in photopolymerization systems, including flexibility and high resolution, and provides examples to illustrate how Raman spectroscopy can be used to monitor photopolymerization reactions and understand the impact of monomer chemistry and processing conditions.
Article
Pharmacology & Pharmacy
Sara Fateixa, Helena I. S. Nogueira, Tito Trindade
Summary: Raman imaging with cluster analysis was used to investigate structural and chemical transformations in carbamazepine polymorphs induced by temperature changes, allowing the identification of different polymorphs and degradation products.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2022)
Article
Environmental Sciences
Wanying He, Minxiao Wang, Mengna Li, Zhaoshan Zhong, Hao Chen, Shichuan Xi, Zhendong Luan, Chaolun Li, Xin Zhang
Summary: This study investigated the effect of four common preservation methods on the results of confocal Raman microscopy (CRM) imaging and signals using deep-sea mussels as a model. The results showed that snap-freeze was the most effective method for comprehensive analysis of biomolecular composition, while snap-freeze followed by rapid fixation in methanol was effective in obtaining good morphology in sections. Glutaraldehyde and paraformaldehyde fixation methods were found to be the most effective for overall morphological observation, but less suitable for metabolic studies.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Biochemical Research Methods
Aaron Doug Deen, Heleen M. M. Van Beusekom, Tom Pfeiffer, Mathijs Stam, Dominique De Kleijn, Jolanda Wentzel, Robert Huber, Antonius F. W. Van der Steen, Gijs Van Soest, Tianshi Wang
Summary: Spectroscopic Thermo-elastic Optical Coherence Tomography (TE-OCT) is a label-free, free-space imaging technique that provides dual contrast in optical imaging. By using short laser pulses to induce tissue deformation and measuring the resulting surface displacement, TE-OCT creates images based on optical reflectance and thermo-elastic deformation, allowing for the identification of tissue components through spectroscopic analysis.
BIOMEDICAL OPTICS EXPRESS
(2022)
Article
Chemistry, Physical
Kai Guo, Fan Yang, Tianyao Weng, Jianguo Chen, Jiye Zhang, Jun Luo, Han Li, Guanghui Rao, Jingtai Zhao
Summary: Doping SrTiO3 with La and Sc can change its electrical transport properties and significantly increase the power factor. Additionally, excess Sc can suppress multifrequency phonon transport, leading to lower thermal conductivity and further optimization of thermal transport properties.
Article
Engineering, Chemical
Maximilian Maier, Dunia Abbas, Miriam Komma, Muhammad Solihul Mu'min, Simon Thiele, Thomas Bohm
Summary: This study investigates the application-relevant properties of perfluorinated sulfonic acid (PFSA) membranes using confocal Raman microscopy. The study analyzes the differences in Raman bands and intensity versus equivalent weight, and characterizes ionomer properties such as swelling and water uptake. It also demonstrates the capability of confocal Raman microscopy to characterize composite membranes and resolve individual phases and features.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Article
Engineering, Electrical & Electronic
Stefan Wiefels, Moritz von Witzleben, Michael Huettemann, Ulrich Boettger, Rainer Waser, Stephan Menzel
Summary: The research focuses on maximizing the endurance of ReRAMs by using specific combinations of switching oxide and ohmic electrode metals. A sophisticated programming algorithm is proposed to achieve this goal, and comparisons of ReRAM devices with different OE metals confirm the theoretically predicted trend, providing valuable information for device engineering towards higher endurance.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Editorial Material
Crystallography
Christian Rodenbucher, Kristof Szot
Article
Crystallography
Christian Rodenbuecher, Christo Guguschev, Carsten Korte, Sebastian Bette, Kristof Szot
Summary: Recent research has found that the behavior of SrTiO3 under reducing conditions differs from traditional understanding, as it can transition from an insulating to a metallic state and remain stable. However, samples that have been oxidized at high temperatures cannot be transformed back to a metallic state through reduction, instead exhibiting semiconducting behavior.
Article
Chemistry, Multidisciplinary
Solomon Amsalu Chekol, Stephan Menzel, Rana Walied Ahmad, Rainer Waser, Susanne Hoffmann-Eifert
Summary: The study investigates the switching dynamics of diffusive memristors based on volatile electrochemical metallization (v-ECM) devices, identifying the importance of filament formation and growth process on its relaxation time through analysis of threshold kinetics and filament relaxation.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Editorial Material
Engineering, Electrical & Electronic
Barak Hoffer, Vikas Rana, Stephan Menzel, Rainer Waser, Shahar Kvatinsky
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Biochemistry & Molecular Biology
Christian Rodenbuecher, Yingzhen Chen, Klaus Wippermann, Piotr M. Kowalski, Margret Giesen, Dirk Mayer, Florian Hausen, Carsten Korte
Summary: Protic ionic liquids show promising application prospects in fuel cells by increasing operation temperatures, facilitating water and heat management, and enhancing efficiency. Experimental and theoretical studies reveal a layered structure at the electrolyte-electrode interface, indicating that the presence of water can significantly affect the system's electrochemical performance.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
S. Tappertzhofen, L. Nielen, I Valov, R. Waser
Summary: The memristively programmable transistor design overcomes the tradeoff between long state retention and fast programming speed by using ions for programming, allowing for higher leakage current levels in gate-dielectrics. Experimental validation demonstrates the potential for high programming endurance and retention times, fast programming speeds, and high scalability.
Review
Physics, Condensed Matter
Regina Dittmann, Stephan Menzel, Rainer Waser
Summary: The review focuses on resistive switching devices operating via the bipolar valence change mechanism (VCM), which have high potential for non-volatile memories and neuromorphic computing. These devices consist of an electronically active electrode, a mixed ionic-electronic conducting layer, and an ohmic counter electrode, with switching dependent on the movement of mobile donor ions.
ADVANCES IN PHYSICS
(2021)
Article
Biochemistry & Molecular Biology
Iwona Lazar, Christian Rodenbuecher, Gustav Bihlmayer, Clive A. Randall, Janusz Koperski, Lutz Nielen, Krystian Roleder, Krzysztof Szot
Summary: Long-time electric field action causes chemical degradation in perovskite piezoelectric ceramics. A new method to accelerate this degradation is by exposing the ceramics to DC electric fields under vacuum. The study focuses on a high-quality commercial piezoelectric material based on PbZr1-xTixO3. The resistance changes during electrodegradation, resulting in electrically-induced deoxidation and transformation of the ceramic into a metallic-like material.
Article
Nanoscience & Nanotechnology
Stephan Aussen, Felix Cueppers, Carsten Funck, Janghyun Jo, Stephan Werner, Christoph Pratsch, Stephan Menzel, Regina Dittmann, Rafal Dunin-Borkowski, Rainer Waser, Susanne Hoffmann-Eifert
Summary: In this study, two different switching modes of memristive devices with valence change mechanism were identified: filamentary mode and interfacial mode. The filamentary mode involves Joule heating, while the interfacial mode operates by modulating the accumulation and depletion of oxygen vacancies.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Crystallography
Christian Rodenbuecher, Gustav Bihlmayer, Carsten Korte, Daniel Rytz, Jacek Szade, Kristof Szot
Summary: The insulator-to-metal transition during thermal reduction of perovskites was studied in high-quality BaTiO3 single crystals under ultra-high-vacuum conditions. Surface layer dislocations played a crucial role as easy reduction sites, allowing for the formation of conducting filaments and the transformation into a state of metallic conductivity with minimal oxygen release. The transition was found to be a highly dynamic, non-equilibrium process involving resegregation effects in the surface layer. The metallicity could be preserved upon cooling to the ferroelectric phase, creating a ferroelectric metal, which was attributed to the coexistence of dislocation-based metallic filaments and piezoelectrically active areas.
Article
Crystallography
Marcin Wojtyniak, Christian Rodenbuecher, Benedykt R. Jany, Grzegorz Cempura, Adam Kruk, Franciszek Krok, Krzysztof Szot
Summary: The physical and chemical properties of oxide materials are strongly affected by defect concentration, giving rise to unique electronic, optical, and dielectric properties. SrTiO3 (STO) is a promising material for various applications due to its interesting phenomena, such as a metal-to-insulator transition induced by reduction. Dislocations, which are 1-D defects, play a significant role in its electronic properties. Therefore, we investigate the process of dislocation movement, creation, and annihilation under ion thinning and electron irradiation.
Article
Computer Science, Information Systems
Nils Kopperberg, Stefan Wiefels, Karl Hofmann, Jan Otterstedt, Dirk J. Wouters, Rainer Waser, Stephan Menzel
Summary: In this work, the endurance of 2 Mbit resistive switching random access memories (ReRAMs) from a 16 MBit test-chip is experimentally characterized. Rare failure events where the memory cells become stuck in the low-resistive state (LRS) are observed. Investigations, both experimental and simulation-based, are conducted to understand the underlying mechanisms causing the failure and provide suggestions for improving switching algorithms.
Article
Engineering, Electrical & Electronic
Christopher Bengel, Johannes Mohr, Stefan Wiefels, Abhairaj Singh, Anteneh Gebregiorgis, Rajendra Bishnoi, Said Hamdioui, Rainer Waser, Dirk Wouters, Stephan Menzel
Summary: This study investigates the impact of device and circuit-level effects on VMM in VCM crossbars, highlighting the importance of variability in the low resistive state and the preference for reading in the RESET direction.
NEUROMORPHIC COMPUTING AND ENGINEERING
(2022)
Article
Chemistry, Physical
Christoph Baeumer, Allen Yu-Lun Liang, Urska Trstenjak, Qiyang Lu, Rainer Waser, J. Tyler Mefford, Felix Gunkel, Slavomir Nemsak, William C. Chueh
Summary: The study demonstrates that exposure to air can alter the chemical environment of oxide electrocatalysts, affecting their activity. It is necessary to consider the effects of air exposure on transition metal oxide catalysts.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
