Article
Optics
Fengkai Meng, Xiaodong Yang, Jie Gao
Summary: In this study, the multiphonon-assisted upconversion photoluminescence (UPL) emission in monolayer MoS2 at elevated temperatures was investigated. The results demonstrated an enhancement of the integrated UPL intensity when the temperature increased from 295 K to 460 K, attributed to the increased phonon population and reduced phonon numbers involved in the UPL process. This research reveals the underlying mechanism of phonon-assisted UPL at high temperatures and provides potential applications in display, nanoscale thermometry, anti-Stokes energy harvesting, and optical refrigeration.
Article
Physics, Applied
William Campbell, Serge Galliou, Michael E. Tobar, Maxim Goryachev
Summary: We investigated the electromechanical properties of quartz bulk acoustic wave resonators at extremely low temperatures. By applying a DC bias voltage, we demonstrated broad frequency tuning of high-Q phonon modes in a quartz bulk acoustic wave cavity at cryogenic temperatures. The resonance peak showed a tuning range of more than 100 line-widths without any degradation in the loaded quality factor, which remained high. The observed coefficient of frequency tuning was asymptotic to 3.5 mHz/V per overtone number n, reaching a maximum value of 255.5 mHz/V for the n=73 overtone mode. No degradation in the quality factor was observed for any applied biasing field.
APPLIED PHYSICS LETTERS
(2023)
Article
Green & Sustainable Science & Technology
Moawiah Mubarak, Raizal Saifulnaaz Muhammad Rashid, Mugahed Amran, Roman Fediuk, Nikolai Vatin, Sergey Klyuev
Summary: By adding a combination of fibers, particularly a mix of long and short PP fibers along with ST fibers, the mechanical properties of HPC under elevated temperatures were significantly improved, maintaining the integrity of concrete. Additionally, PP fibers were effective in preventing spalling, while ST fibers were ineffective in mitigating explosive spalling in beam specimens.
Article
Chemistry, Multidisciplinary
Benedikt Haas, Tara M. Boland, Christian Elsaesser, Arunima K. Singh, Katia March, Juri Barthel, Christoph T. Koch, Peter Rez
Summary: Phonon scattering at grain boundaries plays a crucial role in controlling the thermal conductivity of nanoscale devices. This study uses monochromated electron energy loss spectroscopy (EELS) in the scanning transmission electron microscope (STEM) to measure the 60 meV optic mode at grain boundaries in silicon at atomic resolution. The results show the existence of localized phonon modes and support the idea that grain boundaries can act as waveguides.
Article
Materials Science, Multidisciplinary
Bahman Sheikhi, Mehdi Kargarian, Abdollah Langari
Summary: This study investigates the interplay of magnons and phonons in honeycomb and kagome lattices, showing that their coupling significantly redistributes the Berry curvature among bands and leads to significant changes in the thermal Hall conductivity of topological magnons.
Article
Materials Science, Multidisciplinary
Kun Zhou, Xiaoxing Zhong, Qiang Cheng, Xiaohu Wu
Summary: This study proposes the use of ferroelectric/graphene heterostructure systems to achieve actively tunable hybrid plasmon-phonon polariton modes in low-THz frequencies. By adding graphene layers to ferroelectric-based heterostructures, tunable modes are obtained through the hybridization of ferroelectric phonon polaritons and graphene plasmons, allowing for significant regulation of spontaneous emission rates. The study provides valuable insights for achieving tunable plasmon-phonon polariton modes and regulating spontaneous emission rates in low-THz frequencies.
Article
Engineering, Civil
Sabih Ahmad Khan, Haris Ali Khan, Abdullah Khan, Shuaib Salamat, Syed Saad Javaid, Raja Muhammad Awais Khan
Summary: This research investigates the mechanical behavior of CFRP/Al hybrid riveted joints processed by Fused Deposition Modeling (FDM) at elevated temperatures. Both experimental and computational approaches were used. The experimental evaluation included Digital Image Correlation, micro-XCT, and fractographic analysis, while the computational analysis validated the experimental results. The results showed that the joint experienced net-sectioning and secondary bending at room temperature, and different failure modes were observed for each ply orientation. At elevated temperatures, there was a significant reduction in mechanical properties and warping/bending of the plies.
THIN-WALLED STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
D. Belitz, T. R. Kirkpatrick
Summary: In this study, we used kinetic-theory methods to analyze the Landau Fermi-liquid theory and investigate the soft modes in Fermi liquids in the hydrodynamic and the collisionless regimes. The hydrodynamic regime shows that Fermi-liquid theory is consistent with Navier-Stokes hydrodynamics, while the collisionless regime demonstrates the soft continuous mode and the zero-sound excitations. The two families of soft modes have different physical origins and evolve differently with temperature.
Article
Metallurgy & Metallurgical Engineering
Xia Zhou, Zi-fan Liu, Feng Su, Ya-fu Fan
Summary: 3D numerical simulations were conducted to investigate the dynamic tensile response of hybrid CNT and SiC nanoparticle reinforced AZ91D magnesium composites over a temperature range from 25 to 300 degrees C. The results showed that increasing the volume fraction and ratio of hybrid CNTs to SiC nanoparticles improved the overall dynamic tensile properties of the nanocomposites. Additionally, positive strain rate hardening and temperature softening effects were observed under dynamic loading at high temperatures, with the simulation results matching well with experimental data.
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
(2021)
Article
Chemistry, Multidisciplinary
Dipti Jasrasaria, Eran Rabani
Summary: This study developed an atomistic approach for describing exciton-phonon coupling in semiconductor nanocrystals and validated the method's reliability. Experimental results showed that exciton-phonon coupling leads to lattice distortion in nanocrystals, with surface modes playing a significant role in smaller nanocrystals and interior modes dominating in larger systems.
Article
Construction & Building Technology
Lassi Keranen, Matti Kangaspuoskari, Juhani Niskanen
Summary: This research aims to investigate the usage of compression loaded ultrahigh-strength steel components at elevated temperatures and provide design guidelines. Tensile test data for S700 and S960 ultrahigh-strength steels revealed that their capacities against buckling are weaker than assumed at elevated temperatures.
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH
(2021)
Article
Engineering, Environmental
Adrian D. Metzgen, Andreas Dahmke, Markus Ebert
Summary: Increasing groundwater temperatures can accelerate anaerobic corrosion, affecting groundwater remediation techniques using zero-valent iron. Different ZVIs show varying corrosion rates at different temperatures, with surface precipitates playing a role in passivation and affecting long-term corrosion rates.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Chemical
Qiushi Xu, Xiaoping Guan, Ning Yang
Summary: This study experimentally investigates the fluidization behavior of polyethylene particles in an elevated-temperature liquid-solid fluidized bed. The swelling of particles is observed to occur in two phases, non-cohesive swelling and cohesive swelling, different from the fluidization of cohesive particles in gas-solid systems. Four regimes are identified through static bed height and pressure drop measurements: stable fluidization, noncohesive-swelling fluidization, cohesive-swelling fluidization, and full defluidization. A phase diagram is developed to demarcate these regimes, and an energy balance model is proposed to predict the initial agglomerating temperature of swelling particles for early warning of abnormal fluidization in practical operations.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Computer Science, Interdisciplinary Applications
Armin Morasaei, Aria Ghabussi, Soheila Aghlmand, Maziar Yazdani, Shahrizan Baharom, Hamid Assilzadeh
Summary: The study focuses on employing intelligent techniques to predict the shear and tensile response of steel-concrete composite floor systems at high temperatures. Results indicate that ELM-GWO technique performs best in predicting split-tensile load, and provides the best estimation of slip value.
ENGINEERING WITH COMPUTERS
(2022)
Article
Chemistry, Multidisciplinary
Patrick Laferriere, Sofiane Haffouz, David B. Northeast, Philip J. Poole, Robin L. Williams, Dan Dalacu
Summary: In this study, high purity single photon emission at 1.31μm was achieved using deterministically positioned InP photonic waveguide nanowires. The single photon collection efficiency at first lens was found to be 27.6%, and the probability of multiphoton emission was 0.021. The performance of the source was also evaluated at different temperatures, showing an increase in multiphoton emission probability with temperature.
Article
Physics, Multidisciplinary
Vadim Grinenko, Shreenanda Ghosh, Rajib Sarkar, Jean-Christophe Orain, Artem Nikitin, Matthias Elender, Debarchan Das, Zurab Guguchia, Felix Brueckner, Mark E. Barber, Joonbum Park, Naoki Kikugawa, Dmitry A. Sokolov, Jake S. Bobowski, Takuto Miyoshi, Yoshiteru Maeno, Andrew P. Mackenzie, Hubertus Luetkens, Clifford W. Hicks, Hans-Henning Klauss
Summary: The study on the superconductivity of strontium ruthenate revealed that applying strain can lead to a splitting between the onset of superconductivity and the breaking of time-reversal symmetry, indicating a possible chiral d-wave order parameter. Furthermore, the appearance of bulk magnetic order was observed under higher uniaxial stress above a critical pressure in Sr2RuO4.
Article
Chemistry, Physical
Yu-Xiao Jiang, Jia-Xin Yin, M. Michael Denner, Nana Shumiya, Brenden R. Ortiz, Gang Xu, Zurab Guguchia, Junyi He, Md Shafayat Hossain, Xiaoxiong Liu, Jacob Ruff, Linus Kautzsch, Songtian S. Zhang, Guoqing Chang, Ilya Belopolski, Qi Zhang, Tyler A. Cochran, Daniel Multer, Maksim Litskevich, Zi-Jia Cheng, Xian P. Yang, Ziqiang Wang, Ronny Thomale, Titus Neupert, Stephen D. Wilson, M. Zahid Hasan
Summary: The study reveals an unconventional chiral charge order in KV3Sb5, a material with both a topological band structure and a superconducting ground state, using high-resolution scanning tunnelling microscopy. A 2 x 2 superlattice structure is observed in the experiment, along with an energy gap opening and charge modulation across the Fermi level.
Article
Materials Science, Multidisciplinary
Z. Guguchia, H. Zhou, C. N. Wang, J-X Yin, C. Mielke, S. S. Tsirkin, I Belopolski, S-S Zhang, T. A. Cochran, T. Neupert, R. Khasanov, A. Amato, S. Jia, M. Z. Hasan, H. Luetkens
Summary: The study investigates the magnetic correlations in the kagome magnet Co3Sn2-xInxS2 as a function of In-doping, revealing a quantum phase transition from ferromagnetic to helimagnetic state. The non-monotonous variations of the topological Hall response in the system are driven by the diversity of interactions in the magnetic kagome lattice.
NPJ QUANTUM MATERIALS
(2021)
Article
Physics, Multidisciplinary
Debarchan Das, Ritu Gupta, Christopher Baines, Hubertus Luetkens, Dariusz Kaczorowski, Zurab Guguchia, Rustem Khasanov
Summary: The study found that the superfluid density in α-PdBi2 exhibits a linear relation with Tc, suggesting a possible crossover from Bose-Einstein to Bardeen-Cooper-Schrieffer like condensation in this topological superconductor.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Ilya Belopolski, Tyler A. Cochran, Xiaoxiong Liu, Zi-Jia Cheng, Xian P. Yang, Zurab Guguchia, Stepan S. Tsirkin, Jia-Xin Yin, Praveen Vir, Gohil S. Thakur, Songtian S. Zhang, Junyi Zhang, Konstantine Kaznatcheev, Guangming Cheng, Guoqing Chang, Daniel Multer, Nana Shumiya, Maksim Litskevich, Elio Vescovo, Timur K. Kim, Cephise Cacho, Nan Yao, Claudia Felser, Titus Neupert, M. Zahid Hasan
Summary: The study reports the magnetic manipulation of Weyl fermions in the kagome spin-orbit semimetal Co3Sn2S2, showing the collapse of spin-orbit-gapped ferromagnetic Weyl loops into paramagnetic Dirac loops under suppression of the magnetic order. The disappearance of topological Fermi arcs in the paramagnetic phase indicates the annihilation of exchange-split Weyl points, suggesting new opportunities for engineering topology under correlated order parameters.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Ritu Gupta, Debarchan Das, Charles Hillis Mielke, Zurab Guguchia, Toni Shiroka, Christopher Baines, Marek Bartkowiak, Hubertus Luetkens, Rustem Khasanov, Qiangwei Yin, Zhijun Tu, Chunsheng Gong, Hechang Lei
Summary: The recently discovered kagome superconductor CsV3Sb5 exhibits multi-band nature and anisotropic superconducting properties with a two-gap (s + s)-wave symmetry, while maintaining time reversal symmetry.
NPJ QUANTUM MATERIALS
(2022)
Article
Multidisciplinary Sciences
Sara A. Lopez-Paz, Zurab Guguchia, Vladimir Y. Pomjakushin, Catherine Witteveen, Antonio Cervellino, Hubertus Luetkens, Nicola Casati, Alberto F. Morpurgo, Fabian O. von Rohr
Summary: CrSBr is a promising two-dimensional magnet with complex magnetic behavior and pronounced two-dimensional character at low temperatures. Its properties are ultimately caused by its mixed-anion character.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Z. Guguchia, C. Mielke, D. Das, R. Gupta, J. -X. Yin, H. Liu, Q. Yin, M. H. Christensen, Z. Tu, C. Gong, N. Shumiya, Md Shafayat Hossain, Ts Gamsakhurdashvili, M. Elender, Pengcheng Dai, A. Amato, Y. Shi, H. C. Lei, R. M. Fernandes, M. Z. Hasan, H. Luetkens, R. Khasanov
Summary: In this study, pressure-tuned and ultra-low temperature muon spin spectroscopy was used to uncover the unconventional nature of superconductivity in RbV3Sb5 and KV3Sb5. It was found that at ambient pressure, time-reversal symmetry breaking charge order was observed in RbV3Sb5, and the superconducting state displayed a nodal energy gap and reduced superfluid density. Applying pressure suppressed the charge-order transitions, increased the superfluid density, and progressively evolved the superconducting state from nodal to nodeless. The optimal superconductivity state was found to break time-reversal symmetry. These results offer unique insights into the nature of the pairing state and highlight the tunable nodal kagome superconductivity competing with time-reversal symmetry-breaking charge order.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Yigui Zhong, Jinjin Liu, Xianxin Wu, Zurab Guguchia, J. -x. Yin, Akifumi Mine, Yongkai Li, Sahand Najafzadeh, Debarchan Das, Charles Mielke, Rustem Khasanov, Hubertus Luetkens, Takeshi Suzuki, Kecheng Liu, Xinloong Han, Takeshi Kondo, Jiangping Hu, Shik Shin, Zhiwei Wang, Xun Shi, Yugui Yao, Kozo Okazaki
Summary: The newly discovered kagome superconductors offer a promising platform to explore the interplay between band topology, electronic order, and lattice geometry. However, the nature of the superconducting ground state and the electron pairing symmetry in this system is still not well understood. In this study, we directly observed a nodeless and nearly isotropic superconducting gap in the momentum space of two different kagome superconductors using high-resolution and low-temperature angle-resolved photoemission spectroscopy. The unique properties of the superconducting gap are independent of charge order in the normal state. This comprehensive characterization provides essential information about the electron pairing symmetry in kagome superconductors and advances our understanding of superconductivity and intertwined electronic orders in quantum materials.
Article
Multidisciplinary Sciences
Kohei Matsuura, Masaki Roppongi, Mingwei Qiu, Qi Sheng, Yipeng Cai, Kohtaro Yamakawa, Zurab Guguchia, Ryan P. Day, Kenji M. Kojima, Andrea Damascelli, Yuichi Sugimura, Mikihiko Saito, Takaaki Takenaka, Kota Ishihara, Yuta Mizukami, Kenichiro Hashimoto, Yilun Gu, Shengli Guo, Licheng Fu, Zheneng Zhang, Fanlong Ning, Guoqiang Zhao, Guangyang Dai, Changqing Jin, James W. Beare, Graeme M. Luke, Yasutomo J. Uemura, Takasada Shibauchi
Summary: Iron-chalcogenide superconductors FeSe1-xSx have unique electronic properties and the nature of superconductivity with nematicity is important for understanding unconventional superconductivity. Recent experiments show that the superconducting state in FeSe1-xSx breaks time-reversal symmetry and exhibits ultranodal pair state. The presence of broken TRS and suppressed superfluid density suggests the existence of two different superconducting states separated by the nematic critical point.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Review
Materials Science, Multidisciplinary
Z. Guguchia, R. Khasanov, H. Luetkens
Summary: Kagome lattices are intriguing and rich platforms for studying the intertwining of topology, electron correlation, and magnetism. In this review, recent experimental progress on superconductivity and magnetic fingerprints of charge order in kagome-lattice systems is discussed. The systems include AV(3)Sb(5), LaRu3Si2, and CeRu2, which exhibit unique properties such as time-reversal symmetry-breaking charge ordered state, unconventional superconductivity, and rare nodeless magnetic kagome superconductivity.
NPJ QUANTUM MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Debarchan Das, Karolina Gornicka, Zurab Guguchia, Jan Jaroszynski, Robert J. Cava, Weiwei Xie, Hubertus Luetkens, Tomasz Klimczuk
Summary: The study investigates the superconducting properties of NbIr2B2, a noncentrosymmetric compound. Results demonstrate fully-gapped s-wave superconductivity and a high upper critical field, indicating the preservation of time-reversal symmetry in the superconducting state.
Article
Multidisciplinary Sciences
Jaume Meseguer-Sanchez, Catalin Popescu, Jose Luis Garcia-Munoz, Hubertus Luetkens, Grigol Taniashvili, Efren Navarro-Moratalla, Zurab Guguchia, Elton J. G. Santos
Summary: The translation discusses the coexistence of monoclinic and rhombohedral crystal phases in CrI3, leading to its magnetic behavior change between bulk and thin layers. The authors' findings reveal the continuous transformation of different magnetostructural phases in CrI3 at different temperatures.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
S. Holenstein, F. Hummel, Z. Guguchia, S. Kamusella, N. Barbero, H. Ogino, Z. Shermadini, R. Khasanov, A. Amato, T. Shiroka, H-H Klauss, E. Morenzoni, D. Johrendt, H. Luetkens
Summary: The relationship between magnetism and superconductivity in Sr2VO3FeAs under pressure undergoes a complex evolution, with a possible cooperative coupling between superconducting and magnetic orders as the pressure changes.
Article
Materials Science, Multidisciplinary
Debarchan Das, D. T. Adroja, M. R. Lees, R. W. Taylor, Z. S. Bishnoi, V. K. Anand, A. Bhattacharyya, Z. Guguchia, C. Baines, H. Luetkens, G. B. G. Stenning, Lei Duan, Xiancheng Wang, Changqing Jin
Summary: The superconducting gap structure of the topological superconductor candidate ZrRuAs with a noncentrosymmetric crystal structure was investigated, revealing bulk superconductivity and consistent with an isotropic s-wave gap model. The superconductivity is in the dirty limit, and time-reversal symmetry is preserved in the superconducting state, as indicated by the muon-spin relaxation rate data.
