Article
Materials Science, Multidisciplinary
Aleksandr I. Gusev
Summary: For the first time, the elastic constants of ZrCy zirconium carbide are determined as functions of the carbon content y. The elastic stiffness constants of disordered ZrCy carbide decrease with the defectiveness of the carbon sublattice. An increase in the deviation from stoichiometry results in a slight decrease in elastic anisotropy. The Vickers hardness and Debye temperature of polycrystalline ZrCy carbide increase nonlinearly with increasing carbon content y.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2023)
Article
Materials Science, Ceramics
Jing Hu, Heteng Fan, Songji Wu, Liguo Tang, Lei Qin, Wenyu Luo
Summary: In this study, the temperature dependence of the elastic and piezoelectric properties of a BaTiO3 ceramic sample was determined using resonant ultrasound spectroscopy. The clamped dielectric constants were also measured using an impedance analyzer. The results showed that only one sample was used to guarantee the self-consistency and reliability of the results.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Multidisciplinary
L. Debache, Y. Medkour, F. Djeghloul, K. Haddadi, S. Berri, M. Kharoubi, N. Bouarissa, N. Guechi, A. Roumili
Summary: Ab initio calculations based on density functional theory are used to investigate the mechanical, electronic, optical and transport properties of Ca5Si2N6 and Sr5Ge2N6 nitrides. The results show that these compounds are thermodynamically stable, with Ca5Si2N6 having the best stability. The electronic properties reveal that these nitrides are semiconductors, with Ca5Si2N6 having a direct energy gap of 3.55 eV. The optical response analysis suggests potential applications for Ca5Si2N6 and Sr5Ge2N6, and the thermo-electric properties indicate that these nitrides are favorable candidates for thermoelectric applications at low and room temperatures.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Chemistry, Multidisciplinary
Nataliya A. Sakharova, Jorge M. Antunes, Andre F. G. Pereira, Bruno M. Chaparro, Jose Fernandes
Summary: This study focuses on the elastic properties of non-carbon nanotubes based on compounds of the 13th group of the periodic table. The research reveals that these nanotubes are more suitable candidates than carbon nanotubes for building novel nano-devices, and proposes a robust methodology to calculate the surface elastic moduli of phosphide nanotubes.
Article
Materials Science, Multidisciplinary
Jin Zhang, Jeffrey M. McMahon
Summary: The temperature-dependent elastic constants of ZrC and HfC show changes with temperature, but some constants remain nearly temperature-independent. Further exploration and discussion on the temperature effects on various mechanical properties provide insights into the performance of these materials at elevated temperatures. The vibrational component of the free energy is found to be important in calculating mechanical properties accurately at high temperatures.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Physics, Applied
Hiroshi Fukui, Akira Yoneda, Seiji Kamada, Hiroshi Uchiyama, Naohisa Hirao, Alfred Q. R. Baron
Summary: In this study, the single crystal elasticity of Ta under high pressures was measured using inelastic x-ray scattering, and the density of Ta was measured using x-ray diffraction. By combining the bulk modulus and density, an equation of state of Ta was obtained as a primary scale. The Vinet equation was fitted to the pressure-volume data, and it was found to be consistent with previous work and a recent ruby scale.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Physical
Tor Sewring, Marjolein Dijkstra
Summary: Using Onsager-Straley's theory, this study investigates the cholesteric pitch of cellulose nanocrystal (CNC) suspensions. The research reveals that the twisting of chiral bundles significantly affects the helical twisting of the cholesteric phase. Moreover, the average particle length and length polydispersity have a substantial impact on strongly twisted bundles but minimal effects on weakly twisted ones.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Weimin Dong, Yingjie Sun, Biao Wang, Mengqi Zhu, Jing Li, Xinguang Xu, Jiyang Wang
Summary: The borate piezoelectric crystal BTBO was grown successfully using the TSSG method. It exhibits high longitudinal piezoelectric coefficient and resistivity, as well as good piezoelectric temperature stability, making it a potential candidate for piezoelectric applications.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Chemistry, Physical
Lian-Cai An, Chen Zhao, Ying Zhao, Ying Zhang, Kai Li, Alessandro Stroppa, Wei Li, Xian-He Bu
Summary: This study reports the synthesis of a pair of one-dimensional enantiomorphic hybrid metal halide piezoelectrics and their applications in piezoelectric energy harvesting and sensing. These chiral piezoelectric materials possess low elastic properties and high piezoelectric constants, making them suitable for capturing and sensing piezoelectric energy with excellent performance and stability. Therefore, chiral hybrid metal halides hold great potential in intelligent wearable and sensing devices.
Article
Multidisciplinary Sciences
Johannes Dickmann, Jan Meyer, Mika Gaedtke, Stefanie Kroker
Summary: This paper presents a study on the temperature dependent photo-elastic coefficient in single-crystal silicon at a wavelength of 1550 nm. The results show a significant difference in photo-elasticity between different crystal orientations, and the coefficient's absolute value increases with decreasing temperature. These findings provide valuable insights into the photo-elastic properties of silicon and its behavior under varying mechanical stress.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
Graeme W. Milton
Summary: This study examines the bulk and shear moduli of planar polycrystals built from a single crystal, providing conclusions on achievable microstructures through hierarchical laminates. Algorithms have been proposed, but it is uncertain whether they always succeed in achieving all points in the rectangle defined by the bounds.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2021)
Article
Acoustics
Paul R. Geimer, T. J. Ulrich, Luke B. Beardslee, Mathew L. Hayne, Marcel C. Remillieux, Tarik A. Saleh, Franz J. Freibert
Summary: Understanding the elastic properties of materials is crucial for safe and predictable performance. This study aimed to expand the capabilities of resonant ultrasound spectroscopy (RUS) to characterize isotropic multi-material samples. Through numerical simulations and experimental testing, the study successfully identified the elastic properties of multi-material samples using genetic algorithm inversion and mode matching. This advancement enables the inspection and evaluation of complex composite samples in situ.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2022)
Article
Materials Science, Multidisciplinary
F. Djeghloul, Y. Medkour, M. Kharoubi, N. Bouarissa, A. Roumili
Summary: The electronic structure, optical and thermodynamic properties of M3GeMgN4 (M = Sr or Ba) nitrides were investigated using first-principles calculations. The results show good agreement with experimental data in terms of equilibrium lattice parameters and inter-atomic bond-lengths. The compounds were found to be mechanically stable and elastically soft, ductile and anisotropic. Both Sr3GeMgN4 and Ba3GeMgN4 exhibit semiconductor behavior with respective energy gaps of 1.476 eV and 1.194 eV. The chemical bonding in these semiconductors is primarily covalent, originating from hybridized states of Ge-N and Mg-N. The nitrides display moderate dielectric properties and high absorbance in the visible and UV range, making them suitable for optoelectronic applications. Phononic dispersion curves confirm the dynamical stability of the crystals.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2023)
Article
Chemistry, Physical
Ahmad A. Mubarak, Saad Tariq
Summary: This article presents the structural, electronic, magnetic, mechanical, and optical attributes of SmFeO(3) under pressure up to 80 GPa, revealing changes in some properties of the compound with increasing pressure. The potential application value of the compound in spintronic industry and piezoelectric sensors is also proposed.
INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY
(2021)
Article
Physics, Condensed Matter
Aleksandr I. Gusev
Summary: The elastic properties of cubic Nb3O3 monoxide were studied using density functional theory, showing slight anisotropy. The hardness and Debye temperature of polycrystalline cubic Nb3O3 monoxide were determined.
SOLID STATE COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
L. Konczewicz, E. Litwin-Staszewska, M. Zajac, H. Turski, M. Bockowski, D. Schiavon, M. Chlipala, M. Iwinska, P. Nita, S. Juillaguet, S. Contreras
Summary: This paper presents a comparative study of electron transport phenomena in heavily doped n-type gallium nitride above the Mott transition with silicon and germanium. The samples were grown using molecular beam epitaxy, metal-organic vapor phase epitaxy, and halide vapor phase epitaxy. The temperature dependence of resistivity and Hall Effect was measured from 10 K to 650 K. The study of the electrical transport properties at sub-room temperatures provides valuable insights into extrinsic material properties and scattering mechanisms. The limitations of the applied models are also discussed.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Physical
Mikolaj Amilusik, Marcin Zajac, Tomasz Sochacki, Boleslaw Lucznik, Michal Fijalkowski, Malgorzata Iwinska, Damian Wlodarczyk, Ajeesh Kumar Somakumar, Andrzej Suchocki, Michal Bockowski
Summary: The co-doping of manganese and carbon in gallium nitride crystals grown by halide vapor phase epitaxy was investigated in terms of their structural, optical, and electrical properties. The results showed the significant roles of manganese and carbon in the co-doped gallium nitride crystals.
Article
Crystallography
Karolina Grabianska, Robert Kucharski, Tomasz Sochacki, Jan L. Weyher, Malgorzata Iwinska, Izabella Grzegory, Michal Bockowski
Summary: The results of basic ammonothermal crystallization of gallium nitride are discussed, focusing on stress formation and defect formation. Different positions of gallium nitride grown in the crystallization zone are examined, and the interfaces between native ammonothermal seeds and new-grown layers are investigated. Based on the obtained results, a model of stress and defect formation is presented, along with proposed solutions for improving the structural quality of ammonothermal gallium nitride crystals.
Review
Chemistry, Multidisciplinary
Damian Wlodarczyk, Mikolaj Amilusik, Katarzyna M. Kosyl, Maciej Chrunik, Krystyna Lawniczak-Jablonska, Michal Strankowski, Marcin Zajac, Volodymyr Tsiumra, Aneta Grochot, Anna Reszka, Andrzej Suchocki, Tomasz Giela, Przemyslaw Iwanowski, Michal Bockowski, Hanka Przybylinska
Summary: This comprehensive work presents two novel rock-salt-type minerals synthesized through high-temperature solid-state reaction in inert gases. The studies focus on the synthesis of undoped structures and their polymorphism in different conditions, as well as the physicochemical properties after doping with rare-earth ions. Various analytical techniques were employed to thoroughly describe any possible changes within these materials.
Article
Chemistry, Physical
Tomasz Sochacki, Robert Kucharski, Karolina Grabianska, Jan L. Weyher, Malgorzata Iwinska, Michal Bockowski, Lutz Kirste
Summary: This paper presents a detailed investigation into the basic ammonothermal growth process of GaN, focusing on the crystallization on a native seed with an intentionally varying off-cut. The study aims to answer fundamental questions related to the crystallographic planes, growth rates in different directions, and the influence of seed off-cut. Various characterization methods were employed, leading to the creation of a growth model for ammonothermal GaN crystal. The findings contribute to a better understanding of the basic crystal growth process of GaN using the ammonothermal method.
Article
Chemistry, Physical
Ashfaq Ahmad, Pawel Strak, Pawel Kempisty, Konrad Sakowski, Jacek Piechota, Yoshihiro Kangawa, Izabella Grzegory, Michal Leszczynski, Zbigniew R. R. Zytkiewicz, Grzegorz Muziol, Eva Monroy, Agata Kaminska, Stanislaw Krukowski
Summary: Polarization doping in a GaN-InN system with a graded composition layer was studied using ab initio simulations. The electric charge volume density in the graded concentration part was determined by spatial potential dependence. The polarization difference in the GaN-InN system was changed by piezoelectric effects and showed potential applications in blue and green laser and light-emitting diode design.
Article
Chemistry, Multidisciplinary
Aleksander Szpakiewicz-Szatan, Szymon Starzonek, Tomasz K. Pietrzak, Jerzy E. Garbarczyk, Sylwester J. Rzoska, Michal Bockowski
Summary: A new nanocomposite material was synthesized from glass of NaFePO4 composition using high pressure processing. The sample's thermal, structural, electrical, and dielectric properties were characterized by DTA, XRD, and BDS techniques. The high-pressure-high-temperature treatment significantly increased the electrical conductivity by two orders of magnitude compared to the initial glass, and this effect was stronger than the lithium analogue. This enhancement was attributed to enhanced electron hopping in the pressure-treated samples according to Mott's theory. The nanocrystalline composite consisted of NASICON and alluaudite phases, which could serve as potential cathode materials for Na batteries.
Article
Materials Science, Ceramics
Szymon Starzonek, Aleksander Szpakiewicz-Szatan, Sylwester J. Rzoska, Aleksandra Drozd-Rzoska, Michal Bockowski, Tomasz K. Pietrzak, Jerzy E. Garbarczyk
Summary: This paper investigates systems formed in a solid glassy state after a nanocrystallization process above the glass temperature. It analyzes the electric conductivity and relaxation processes after treatment under high temperature and high pressure. The results show an increase in density, electric conductivity, and qualitative changes in dynamics processes. The paper also introduces a new method for data analysis based on the activation and critical-like nature of processes. It provides evidence of pressure evolution of the glass and crystallization temperatures, indicating the unique possibility of maxima and crossovers.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2023)
Article
Physics, Condensed Matter
Igor Prozheev, Malgorzata Iwinska, Tomasz Sochacki, Michal Bockowski, Rene Bes, Filip Tuomisto
Summary: The results of positron lifetime and X-ray absorption spectroscopy in Si-doped GaN crystals, grown by HVPE, are presented. High Si concentration leads to significant compensation effects. Ga vacancies are insufficient as compensation centers and other acceptor-like impurities are present at much lower concentrations than Si. X-ray absorption shows that the local environment of Si dopants is different in compensated samples. Simulated spectra suggest that Si has a higher presence in the nearest local environment in compensated spectra, indicating autocompensation of Si dopants in high Si content GaN samples grown by HVPE.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Emi Kano, Ritsuo Otsuki, Koki Kobayashi, Keita Kataoka, Kacper Sierakowski, Michal Bockowski, Masahiro Nagao, Tetsuo Narita, Tetsu Kachi, Nobuyuki Ikarashi
Summary: Transmission electron microscopy is used to observe dislocation loops in Mg-ion-implanted GaN during annealing. The diffusion of native defects is slowed down at higher pressure during annealing. Secondary ion mass spectrometry shows that annealing at higher pressure retards the migration of Mg and increases its concentration in the ion-implanted region. These findings provide a design principle for the annealing process to activate ion-implanted Mg in GaN.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
Article
Chemistry, Physical
Tomasz Sochacki, Robert Kucharski, Karolina Grabianska, Jan L. L. Weyher, Magdalena A. A. Zajac, Malgorzata Iwinska, Lutz Kirste, Michal Bockowski
Summary: A detailed analysis was conducted on the morphology of gallium nitride crystal growth obtained by ammonothermal and halide vapor phase epitaxy methods. The study aimed to determine the source of triangular planar defects visible in X-ray topography as areas with locally different lattice parameters. It was found that these defects are related to growth hillocks, and particular attention was paid to analyzing the merging of hillocks and its consequences. The nature and cause of these defects were determined, with the angle formed between adjacent hillocks being identified as a key factor.
Article
Chemistry, Physical
Jacek Piechota, Stanislaw Krukowski, Bohdan Sadovyi, Petro Sadovyi, Sylwester Porowski, Izabella Grzegory
Summary: This study investigates the behavior of GaN crystal at high temperatures and pressures, revealing that it undergoes thermal decomposition and congruent melting. Simulation results are in excellent agreement with experimental data, providing valuable insights into the physical properties of GaN.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Pawel Kempisty, Ashfaq Ahmad, Pawel Strak, Konrad Sakowski, Anna Kafar, Jacek Piechota, Stanislaw Krukowski
Summary: Indium incorporation on the GaN surface was analyzed in the context of InGaN growth by MOVPE. The results showed that the adsorption energy strongly depends on the electronic properties of the surface, and the increase in hydrogen pressure leads to an increase in the equilibrium pressures of indium, resulting in reduced indium incorporation.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Review
Physics, Applied
Maciej Matys, Kazuki Kitagawa, Tetsuo Narita, Tsutomu Uesugi, Michal Bockowski, Jun Suda, Tetsu Kachi
Summary: This review briefly summarizes the major challenges and recent progress in the development of GaN Junction Barrier Schottky (JBS) diodes using selective-area p-type doping with ion implantation and ultra high-pressure annealing (UHPA) process. The high-performance JBS diodes demonstrated superior electrical characteristics and nondestructive breakdown.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Yuki Hatakeyama, Tetsuo Narita, Michal Bockowski, Tetsu Kachi, Masamichi Akazawa
Summary: The gap states near the conduction band edge in Mg-ion-implanted GaN and Al2O3 interface were investigated, and the gap state density can be improved through capless ultra-high-pressure annealing.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
