Article
Chemistry, Physical
Na-Na Zhang, Xiu-Xi Jiang, Ya-Ni Wang, Xiao-Ru Pan, Yuan-Yuan Zhang, Bing Liu, Yu-Guo Yang, Xu-Ping Wang
Summary: In this study, series of La3Ga5SiO14:Pr3+ phosphors were synthesized and characterized. The results showed that the Pr3+ doping did not significantly alter the crystal structure and phonon properties of La3Ga5SiO14 host. The phosphors exhibited strong absorption bands and emitted white light.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
S. Restelli, B. Albini, S. Bonomi, M. Bini, M. C. Mozzati, P. Galinetto
Summary: ZnFe2O4 nanostructures are widely used for their functional properties in various applications. It is important to monitor and control their response to external stimuli and to understand the relation with their properties to avoid performance worsening.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Fanghua Cheng, Junwei Huang, Feng Qin, Ling Zhou, Xueting Dai, Xiangyu Bi, Caorong Zhang, Zeya Li, Ming Tang, Caiyu Qiu, Yangfan Lu, Huiyang Gou, Hongtao Yuan
Summary: Strain engineering is a powerful technique for modulating the exotic properties arising from the atomic structure of materials. In the crystal structure of silicon diphosphide (SiP2), strain engineering can be used to manipulate the optical properties and band gap energy of quasi-1D P-P chains, providing opportunities for potential optical applications.
Review
Chemistry, Multidisciplinary
Charalampos A. Londos, Alexander Chroneos, Efstratia N. Sgourou, Ioannis Panagiotidis, Theoharis Angeletos, Marianna S. Potsidi
Summary: Crystalline silicon is a crucial material in the semiconductor industry, and impurities and defects can affect its properties. This review focuses on the impact of isovalent doping on oxygen-related and carbon-related defects in electron-irradiated silicon, discussing recent experimental results and theoretical studies.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Physical
Hyungsub Lim, Hyo Chan Lee, Kilwon Cho
Summary: Graphene/Cu composites show promise as future electrode materials due to their mechanical, electrical, and thermal stability. However, the presence of graphene accelerates oxidation of the underlying Cu surface, which affects the properties of the composites. Therefore, it is critical to investigate the effects of Cu oxidation on the interfacial properties of graphene/Cu composites.
Article
Physics, Applied
Yu-Chen Chang, Bipul Das, Yu-Fan Chiang, Wen-Hao Chang, Yen-Chun Chen, Rahul Kesarwani, Wen-Cheng Ke, Yann-Wen Lan, Ting-Hua Lu
Summary: Displacement in conventional Raman spectroscopy can be caused by an increase in material layers or strain variation. Polarization-resolved Raman spectroscopy provides a method to distinguish between them. This study uses polarization-resolved Raman spectroscopy and numerical analysis to investigate strained graphene induced by different substrates. The research shows that the polarization properties of scattered light in strained graphene are different from unstrained graphene due to phonon polarization deformation caused by different strengths of substrate coupling. This research provides an efficient quantitative method to explore strain anisotropy in two-dimensional materials, which is important for the development of straintronics in the future.
APPLIED PHYSICS LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Kao-Peng Min, Cheng-Ying Li, Ting-Jia Chang, Sheng-Yuan Chu
Summary: The study successfully improved the performance of AlN-based RRAM through silicon doping into AlN films, resulting in increased on/off ratio, decreased set voltage, and enhanced resistance switching stability.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Hang Xin, Jingyun Zhang, Cuihong Yang, Yunyun Chen
Summary: This paper proposes an efficient method to analyze the inhomogeneity of 2D materials by combining Raman spectroscopy and unsupervised k-means clustering analysis. The method can reveal both the inhomogeneity and spatial distribution of 2D materials, and has been successfully applied to MoS2, WS2, and WSe2 samples.
Article
Physics, Applied
Yiwen Zhang, Chuan Zhou, Ying Zhu, Guangrui (Maggie) Xia, Lei Li, Rui-Tao Wen
Summary: Surface thermal annealing can be used to evaluate the threading dislocation densities in heteroepitaxial layers, and the origin of thermal pits induced by annealing was found to be the activation of threading dislocations.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Engineering, Chemical
Smita S. Bishoyi, Shantanu K. Behera
Summary: High energy mechanical milling was used to fabricate nanoparticulate Si using Al2O3 grinding media. The optimal milling time for producing well dispersed Si nanoparticles was found to be 13 hours. The strain induced in the materials increased progressively with milling duration, as calculated from X-ray diffractograms and Raman spectrographs.
ADVANCED POWDER TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Subhadip Das, Koyendrila Debnath, Biswanath Chakraborty, Anjali Singh, Shivani Grover, D. V. S. Muthu, U. Waghmare, A. K. Sood
Summary: Understanding of electron-phonon coupling (EPC) in 2D materials through in situ Raman measurements provides insights into their potential applications in nanoelectronics, with research on bilayer MoTe2 highlighting the role of symmetry in determining EPC manifestations.
Article
Materials Science, Multidisciplinary
Vikas Kashyap, Chandra Kumar, Neeru Chaudhary, Navdeep Goyal, Kapil Saxena
Summary: The study investigates the quantum confinement effect in SiNWs fabricated by SIE technique, showing an enhanced optical band gap under UV excitation. The analysis of characteristic features of Raman line-shape helps to understand the mechanism of QC effect, and different models are used to calculate the NCS of SiNWs in the samples. This research suggests a new direction for fabricating optoelectronic devices based on nano-scale light-matter interactions.
Article
Chemistry, Physical
Sucheta Juneja, Sushil Kumar
Summary: The effect of diborane doping on the crystallinity and crystallite size of hydrogenated silicon films was analyzed. It was found that boron doping suppresses silicon crystallization and reduces crystallite sizes.
Article
Chemistry, Multidisciplinary
Kyuyeon Won, Chanwoo Lee, Jaehyuck Jung, Sanghyuk Kwon, Yisehak Gebredingle, Jang Gyun Lim, Moon Ki Kim, Mun Seok Jeong, Changgu Lee
Summary: Graphene, a superstiff and extremely strong material, has been challenging to measure its physical properties under high strains. This research reports a successful measurement of suspended graphene under a biaxial strain as large as 6.1% using AFM-Raman spectroscopy. The Raman signals of graphene's G and 2D bands redshifted significantly, providing an effective methodology to measure variations in the physical properties of atomically thin materials under superhigh strain.
ADVANCED MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Xinyuan Wang, Bin Lu, Haiping Xia
Summary: A novel orthorhombic GdInO3:Eu perovskite red phosphor with good luminescence properties was synthesized. It has wide direct bandgaps and low phonon energies compared to the hexagonal counterpart. The orthorhombic GdInO3:Eu phosphor exhibits stronger emission intensity, a longer fluorescence lifetime, and a higher color purity.
MATERIALS TODAY NANO
(2023)
Article
Physics, Applied
Elias Baron, Martin Feneberg, Rudiger Goldhahn, Michael Deppe, Fabian Tacken, Donat J. As
Summary: By introducing germanium as a donor, free-electron concentrations above 10^(20) cm^(-3) in GaN can be achieved. The use of spectroscopic ellipsometry allows for the determination of free-electron concentration optically, while the Kane model and consideration of Burstein-Moss-shift and band-gap renormalization efficiently describe the measured transition energies.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Physics, Applied
Martin Feneberg, Fatima Romero, Rudiger Goldhahn, Tim Wernicke, Christoph Reich, Joachim Stellmach, Frank Mehnke, Arne Knauer, Markus Weyers, Michael Kneissl
Summary: Investigation on light emitting diode structures emitting in the ultraviolet spectral range reveals defect luminescence bands, with the origin of defect luminescence assigned to certain layers using synchrotron-based photoluminescence excitation spectroscopy. For quantum well structures emitting at different wavelengths, the origins of defect luminescence bands vary depending on the presence of n-type contact AlGaN:Si layers.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Martin Haehsler, Hajnalka Nadasi, Martin Feneberg, Sebastian Marino, Frank Giesselmann, Silke Behrens, Alexey Eremin
Summary: Self-assembly is a crucial mechanism for designing multifunctional materials, especially in soft hybrid materials where components of different natures interact to form structures with specific functions. A novel magnetic hybrid material was demonstrated, showing the manipulation of molecular tilt through a delicate balance between topologically-assisted colloidal self-assembly of magnetic nanoparticles and anisotropic molecular interactions in a liquid crystal matrix.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Physics, Applied
Jona Gruembel, Rudiger Goldhahn, Dae-Woo Jeon, Martin Feneberg
Summary: The Raman excitations of an alpha-Ga2O3 thin film were investigated, and the contributions of different decay mechanisms to the phonon modes were quantified through model calculations. The experimental data can be well described by the applied theoretical models, and the phonon modes of alpha-Ga2O3 show smaller frequency shifts and broadening under temperature variation compared to other materials.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Shaojun Wu, Martin Guttmann, Neysha Lobo-Ploch, Frank Gindele, Norman Susilo, Arne Knauer, Tim Kolbe, Jens Rass, Sylvia Hagedorn, Hyun Kyong Cho, Katrin Hilbrich, Martin Feneberg, Ruediger Goldhahn, Sven Einfeldt, Tim Wernicke, Markus Weyers, Michael Kneissl
Summary: The increase in light extraction efficiency and total output power of UV LEDs after encapsulation with UV-transparent silicone are studied. The simulations and experimental results show that properly placed hemispherical encapsulation can enhance the light extraction efficiency and increase the total output power of the LEDs.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Physical
Vitaly Gorelov, Lucia Reining, Martin Feneberg, Ruediger Goldhahn, Andre Schleife, Walter R. L. Lambrecht, Matteo Gatti
Summary: This article uses V2O5 as an example to explore how charge-transfer excitations combine to form excitons with large binding energy and electron-hole distance, and explains this phenomenon. By combining various methods, consistent results are obtained.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Alexandra Papadogianni, Charlotte Wouters, Robert Schewski, Johannes Feldl, Jonas Lahnemann, Takahiro Nagata, Elias Kluth, Martin Feneberg, Rudiger Goldhahn, Manfred Ramsteiner, Martin Albrecht, Oliver Bierwagen
Summary: In this study, single-crystalline bixbyite (In1-xGax)(2)O-3 films were grown on (111)-oriented yttria-stabilized zirconia substrates using plasma-assisted molecular beam epitaxy. The addition of a pure In2O3 buffer layer between the substrate and (In1-xGax)(2)O-3 alloy improved the film surface smoothness and crystallinity. The distribution of Ga cations in the films was found to be non-uniform, with high Ga density inclusions observed at higher Ga content. The cubic bixbyite phase was preserved in both the matrix and the inclusions.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Physics, Applied
Ramon Cusco, Tomohiro Yamaguchi, Elias Kluth, Rudiger Goldhahn, Martin Feneberg
Summary: The optical properties of a single-phase corundum-structured In2O3 epilayer grown by a mist chemical vapor deposition method have been investigated. Raman scattering and spectroscopic ellipsometry measurements are in good agreement with theoretical calculations, and two distinct absorption onsets are observed in the UV region.
APPLIED PHYSICS LETTERS
(2022)
Article
Crystallography
T. Henksmeier, J. F. Schulz, E. Kluth, M. Feneberg, R. Goldhahn, A. M. Sanchez, M. Voigt, G. Grundmeier, D. Reuter
Summary: This study reports on the remote heteroepitaxy growth of InxGa(1-x)As-layers on transfer graphene covered GaAs substrates by molecular beam epitaxy. The strain relaxation of the layers on graphene was compared to that on bare GaAs, revealing more relaxation and symmetric strain relaxation on graphene.
JOURNAL OF CRYSTAL GROWTH
(2022)
Article
Physics, Applied
Kingsley Egbo, Esperanza Luna, Jonas Laehnemann, Georg Hoffmann, Achim Trampert, Jona Gruembel, Elias Kluth, Martin Feneberg, Ruediger Goldhahn, Oliver Bierwagen
Summary: By combining SnO2 and Sn, we successfully grew phase-pure single-crystalline metastable SnO (001) thin films on Y-stabilized ZrO2 (001) substrates using suboxide molecular beam epitaxy (S-MBE) at a growth rate of about 1.0 nm/min without additional oxygen. These films exhibit epitaxial growth over a wide temperature range of 150 to 450°C. The obtained p-type SnO films at low substrate temperatures show promise for back-end-of-line (BEOL) compatible applications and integration with n-type oxides in pn heterojunctions and field-effect transistors.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Sida Wang, Phil Liebing, Martin Feneberg, Farid M. Sroor, Felix Engelhardt, Liane Hilfert, Sabine Busse, Elias Kluth, Rudiger Goldhahn, Frank T. Edelmann
Summary: A series of new alkynylamidinate complexes of selected first and second row transition metals has been synthesized and fully characterized. Different reactions were employed to obtain various binuclear complexes with different metal-metal bonding. The structures of all the compounds were determined using single-crystal X-ray diffraction and spectroscopic techniques.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Physics, Applied
Elias Baron, Ruediger Goldhahn, Shirly Espinoza, Martin Zahradnik, Mateusz Rebarz, Jakob Andreasson, Michael Deppe, Donat J. As, Martin Feneberg
Summary: We have published a recent study on femtosecond pump-probe absorption edge spectroscopy of cubic GaN, which resulted in the transient dielectric function. In this study, we investigate the time-dependent transition energy between the conduction and valence bands by analyzing pump-probe measurements. By converting transition energies into free-carrier concentrations and assuming electron contributions to be dominant, we model the ultra-fast change and consider various effects such as relaxation, recombination, diffusion, gain-recombination, and temperature effects. Both models provide similar values for the characteristic relaxation time, recombination time, and diffusion coefficient.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Elias Baron, Rudiger Goldhahn, Shirly Espinoza, Martin Zahradnik, Mateusz Rebarz, Jakob Andreasson, Michael Deppe, Donat J. J. As, Martin Feneberg
Summary: An ultra-fast change in the absorption onset of zincblende gallium-nitride (zb-GaN) is observed using time-dependent femtosecond pump-probe spectroscopic ellipsometry. The absorption onset increases due to band filling, while the bandgap decreases due to bandgap renormalization. The optical properties vary from the sample surface to the substrate, which is taken into account by grading analysis.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Volker Lorenz, Phil Liebing, Matthias Mueller, Liane Hilfert, Martin Feneberg, Elias Kluth, Marcel Kuehling, Magnus R. Buchner, Rudiger Goldhahn, Frank T. Edelmann
Summary: A series of brightly colored alkaline earth metal 1,3-dimethylviolurates have been synthesized and characterized. Different colored salts were obtained by neutralizing 1,3-dimethylvioluric acid monohydrate with corresponding metal dihydroxides. The study also discovered new compound structures and mixed-anion salts, expanding the coordination chemistry of violurates and related ligands.
DALTON TRANSACTIONS
(2022)
Article
Materials Science, Multidisciplinary
Jiongyao Wu, Marcel Zoellner, Sebastian Esser, Vijaya Begum, Guenther Prinz, Axel Lorke, Philipp Gegenwart, Rossitza Pentcheva
Summary: The electronic, magnetic, and optical properties of the double perovskite Sr2CoIrO6 under biaxial strain were investigated using density functional theory with Hubbard U term and spin-orbit coupling, revealing that Co and Ir exhibit different spin and orbital moments under varying strain conditions. The band gap shows a nonmonotonic change due to the inclusion of many-body effects, including excitonic effects. The study highlights the complex electronic structure and optical properties of SCIO.
