Article
Chemistry, Multidisciplinary
Yuchun Liu, Tianci Shen, Shuangyi Linghu, Ruilin Zhu, Fuxing Gu
Summary: Excitonic photoluminescence (PL) in monolayer MoS2 can be tailored by electrostatic doping, allowing for the control of both A excitons and B excitons. Gate voltage manipulation results in significant changes in both A-excitonic and B-excitonic PL, with the ratio of B/A excitonic PL showing a 26-fold enhancement. This electrostatic control of excitonic PL holds potential for applications in exciton physics and valleytronics involving B excitons.
NANOSCALE ADVANCES
(2022)
Article
Instruments & Instrumentation
Kang Liang, Zhao Zhang, Gai Wu, Zhiyin Gan, Sheng Liu
Summary: In this paper, an optimization method based on particle swarm optimization, Monte Carlo simulations, and an artificial neural network is proposed to improve the thickness uniformity of molecular beam epitaxial films. The optimum angular distribution of the molecular source and the shape parameters of the crucible inner wall are determined to achieve the best film uniformity.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Physics, Multidisciplinary
Akash Biswas, Bidya Binay Karak, Robert Cameron
Summary: A striking feature of the solar cycle is the migration of sunspots from midlatitudes to the equator over time. The level of activity and width of sunspot belts increase rapidly and then decline, while in the late stages of the cycle, the statistical properties remain the same regardless of the cycle's strength during its rise and maximum phases.
PHYSICAL REVIEW LETTERS
(2022)
Article
Energy & Fuels
Ernest Gyan Bediako, Petra Dancova, Tomas Vit
Summary: In recent years, research on flow boiling heat transfer has gained popularity for understanding its mechanisms and characteristics. This study experimentally investigated the characteristics of flow boiling heat transfer from a single-phase region to a two-phase region. The results showed that nucleate boiling dominated in the low vapor quality region, while convective boiling dominated in the high vapor quality region. The flow patterns observed were slug and intermittent in the low vapor quality region, and annular and mist in the high vapor quality region. Frictional pressure drop increased with increasing mass flux and vapor quality in the two-phase region.
Article
Chemistry, Analytical
Cheng Wang, Lei Guo, Shaotong Zhang, Zihang Fei, Gang Xue, Xiuqing Yang, Jiarui Zhang
Summary: This paper presents a numerical model to investigate the effect of device structure on seawater flow in the processes of marine sediment transport observation and sediment particle capture. The flow velocity distribution inside and outside the capture tube with different screen pore sizes is analyzed, and the simulation results are compared with test results, showing good coincidence. The accurate capture of sediment particles and the optimal capture efficiency of the sediment trap are achieved.
Article
Biodiversity Conservation
Mingjie Xu, Jie Hu, Tao Zhang, Huimin Wang, Xianjin Zhu, Jianlei Wang, Fengting Yang, Hui Zhang, Qianyu Wang
Summary: Studying 12 years of flux data revealed that canopy conductance (gc) varies in response to environmental factors, with humidity and temperature affecting gc. Furthermore, divergent responses of gc to environmental factors were found in different climatic years.
ECOLOGICAL INDICATORS
(2021)
Article
Mechanics
Chong Li, Xiande Fang, Qiumin Dai
Summary: Two-phase pressure drop oscillations during flow boiling were experimentally investigated in a horizontal microchannel with a diameter of 0.9 mm using pure fluid R245fa. The effects of mass flux and heat flux on the oscillations were analyzed, and four types of oscillations were identified. The oscillations were found to be influenced by the flow patterns in the test section and the upstream compressible volume of vapor.
Article
Chemistry, Multidisciplinary
Yi Yu, Xiaoyue Sun, Ran Du, Hongjie Zhang, Dayan Liu, Ying Wang, Xinyu Zhang, Wenyu Zhang, Shuchen Zhang, Jinjie Qian, Yue Hu, Shaoming Huang
Summary: This article introduces the research on growing metal-free SWNT arrays using NaCl as a catalyst. By employing a proper growth strategy, well-defined arrays are obtained. The study also proves the advantage of these metal-free SWNT arrays in preparing stable devices.
Article
Thermodynamics
J. Van Nieuwenhuyse, A. De Meulemeester, S. Lecompte, M. De Paepe
Summary: Knowledge about supercritical heat transfer to refrigerants with horizontal flow is limited and experimental data is lacking. This study aims to close this gap and increase the understanding of supercritical heat transfer by investigating phenomena on larger tube diameters using a novel experimental setup.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Forestry
Sander O. Denham, A. Christopher Oishi, Chelcy F. Miniat, Jeffrey D. Wood, Koong Yi, Michael C. Benson, Kimberly A. Novick
Summary: Plants experience hydraulic stress under conditions of low water availability and/or high atmospheric demand for water. Different species adapt to respond to this stress by closing stomata to maintain leaf water potential (isohydric species) or allowing the potential to decline (anisohydric species). Sensitivity of canopy conductance to soil moisture varies among sites and species, while sensitivity to vapor pressure deficit remains relatively constant.
Review
Chemistry, Multidisciplinary
Boyu Peng, Ruihan Wu, Hanying Li
Summary: Organic semiconductor (OSC) single crystals are promising for flexible electronic/optoelectronic applications due to their high mobility and intrinsic flexibility, but challenges arise in forming large, uniform, and defect-free single crystals. The droplet-pinned crystallization (DPC) method developed in 2012 offers a time- and cost-effective way to grow high-quality OSC single crystals, accelerating studies on charge-transport mechanisms and addressing the general lagging of electron mobility in OSC materials. The method allows flexibility in OSC materials and solvents, facilitating the formation of single-crystal OSC heterojunctions with promising potentials in circuits, photovoltaics, and photodiodes.
ACCOUNTS OF CHEMICAL RESEARCH
(2021)
Article
Forestry
Kelsey N. Bryant, Brett W. Fredericksen, David M. Rosenthal
Summary: The research reveals a spectrum of hydraulic behaviors among co-existing mature temperate tree species, with some exhibiting isohydric behavior and others anisohydric behavior. Understanding these species-specific strategies is important for predicting how temperate forests may respond to changes in climate, especially water availability.
TREES-STRUCTURE AND FUNCTION
(2022)
Article
Geosciences, Multidisciplinary
Xin An, Anton Artemyev, Vassilis Angelopoulos, Andrei Runov, San Lu, Philip Pritchett
Summary: The force balance and configuration transition of the magnetotail current sheet play a crucial role in the onset of substorms in the Earth's magnetosphere. Through particle-in-cell simulations, it is found that the thinning of the current sheet leads to the formation of a nearly one-dimensional magnetic field configuration, driven by plasma pressure nongyrotropy in the ion distributions. The instability and dynamics of such nongyrotropic current sheets, which differ significantly from the commonly studied two-dimensional isotropic configuration, may control the onset of substorms.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Divya Rea, Robert M. Rauber, Huancui Hu, Sarah A. Tessendorf, Steve W. Nesbitt, Brian F. Jewett, Troy J. Zaremba
Summary: This study evaluates the impact of an atmospheric river (AR) on the flux of subtropical moisture and precipitation in Idaho's Salmon River Mountains. The results show that over 70% of the moisture flux and over 80% of the precipitation can be attributed to subtropical moisture within the mountains. This study contributes to a better understanding of how Pacific ARs affect water resources in Idaho's mountain regions.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Thermodynamics
Jiaqi Zhang, Ke Wang, Lanwei Chen
Summary: Experimental investigation on chill-down by the constant rate of liquid oxygen was conducted in a pipe with an inner diameter of 20 mm, upstream of an injector. The study showed that pressure significantly affects the inner wall temperatures on both the Leidenfrost point (LFP) and critical heat flux (CHF), and new correlations were recommended based on the combined data for reliable predictions. Additionally, both pressure and pipe length play important roles in the heat fluxes on LFP and CHF.
APPLIED THERMAL ENGINEERING
(2021)
Article
Nanoscience & Nanotechnology
Hang Chen, Shahidul Asif, Kapildeb Dolui, Yang Wang, Jeyson Tamara-Isaza, V. M. L. Durga Prasad Goli, Matthew Whalen, Xinhao Wang, Zhijie Chen, Huiqin Zhang, Kai Liu, Deep Jariwala, M. Benjamin Jungfleisch, Chitraleema Chakraborty, Andrew F. May, Michael A. McGuire, Branislav K. Nikolic, John Q. Xiao, Mark J. H. Ku
Summary: The study reports on exfoliated flakes of cobalt-substituted Fe5GeTe2 (CFGT) that exhibit magnetism above room temperature. Ferromagnetism at room temperature was observed in CFGT flakes as thin as 16 nm using quantum magnetic imaging. This expands the portfolio of thin room temperature 2D magnet flakes exfoliated from robust single crystals.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Ryan Selhorst, Zhuohang Yu, David Moore, Jie Jiang, Michael A. Susner, Nicholas R. Glavin, Ruth Pachter, Mauricio Terrones, Benji Maruyama, Rahul Rao
Summary: Layered Transition Metal Dichalcogenides (TMDs) are important materials with a diverse range of optoelectronic properties. This study investigates the spatial tailoring of TMDs through electron-beam patterning, achieving high resolution and demonstrating potential for nanoscale functionalization. The modulated properties were found to be dependent on various parameters, and the results were confirmed through spectroscopic analysis and density functional theory modeling. This research provides a robust method for property modulation and functionalization of TMDs at the nanoscale.
Article
Chemistry, Multidisciplinary
Farhan Islam, Yongbin Lee, Daniel M. M. Pajerowski, JinSu Oh, Wei Tian, Lin Zhou, Jiaqiang Yan, Liqin Ke, Robert J. J. McQueeney, David Vaknin
Summary: Magnetic defects play a crucial role in magnetic topological insulators, influencing both the surface transport and bulk magnetic properties. In Bi2Se3-based dilute ferromagnetic (FM) TIs and MnBi2Te4-based antiferromagnetic (AFM) TIs, magnetic defects control the behavior. In Sb2Te3, a fraction of the Mn defects form strong AFM dimer singlets within a quintuple block, while in Sb1-xMnxTe3, the FM correlations are likely driven by magnetic defects in adjacent quintuple blocks.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
J. -q. Yan, M. A. McGuire
Summary: This paper introduces a less well-known vapor transport technique called self-selecting vapor growth, and reports on the growth of transition-metal halides using this technique. The research shows that the self-selecting vapor transport technique can provide large single crystals of transition-metal halides, demonstrating its potential for providing high-quality single crystals of quantum materials.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jierui Liang, Shanchuan Liang, Ti Xie, Andrew F. May, Thomas Ersevim, Qinqin Wang, Hyobin Ahn, Changgu Lee, Xixiang Zhang, Jian-Ping Wang, Michael A. McGuire, Min Ouyang, Cheng Gong
Summary: Exchange bias in van der Waals (vdW) magnets is crucial for magnetoresistive logic and memory devices. We demonstrate a facile method to achieve strong exchange bias in Fe5GeTe2 through atomic layer deposition (ALD) of oxides. By depositing Al2O3, ZnO, and V2O5 on Fe5GeTe2, exchange biases of 300-1500 Oe were obtained at 130 K. We show that the duration of oxidant pulse in each ALD cycle and the oxidant used in the process play a key role in enhancing the exchange bias strength. Our work highlights the importance of ALD-enabled oxidization of Fe5GeTe2 and establishes ALD of oxides as a promising approach for creating giant exchange bias in vdW magnets.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Sabine M. Neumayer, Nora Bauer, Sergey Basun, Benjamin S. Conner, Michael A. Susner, Maxim O. Lavrentovich, Petro Maksymovych
Summary: The polarization dynamics in ferroelectric materials depends on the potential energy landscape of the order parameter. Ferroelectrics have the unique property of having more than two potential wells, resulting in complex energy landscapes. In this study, the presence of a triple-well potential in the Sn2P2S6 compound was revealed using scanning probe microscopy and theoretical simulations. The metastable zero polarization state in Sn2P2S6 was accessed through a gradual switching process and was found to be stabilized over a wide range of electric fields. The observed zero polarization state originated from the kinetic stabilization of the nonpolar state of the triple-well.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Sang Yong Song, Chengyun Hua, Luke Bell, Wonhee Ko, Hans Fangohr, Jiaqiang Yan, Gabor B. Halasz, Eugene F. Dumitrescu, Benjamin J. Lawrie, Petro Maksymovych
Summary: New pathways are needed to control the morphology and dynamics of superconducting vortex lattices in order to transform them into a computing platform. It has been discovered that nematic twin boundaries can align superconducting vortices in adjacent terraces. Different structural phases of the vortex lattice can be assumed by varying the density and morphology of the twin boundaries. These findings have implications for the design and control of strain-based topological quantum computing architectures.
Article
Crystallography
Michael A. A. McGuire, Eleanor M. M. Clements, Qiang Zhang, Satoshi Okamoto
Summary: This article investigates the properties of Pt3X2 (X = In and Tl), which adopt a double-layer kagome net structure related to topologically nontrivial compounds Fe3Sn2 and V3Sb2. Through various measurements and calculations, it is found that the Fermi levels of Pt3X2 lie in pseudogaps, and several bands contribute to transport. Despite the extended nature of the Pt 5d states, the observed moderately large and non-saturating magnetoresistance values and quantum oscillations suggest the presence of the kagome nets in Pt.
Article
Crystallography
Duncan H. H. Moseley, Craig A. A. Bridges, Luke L. L. Daemen, Qiang Zhang, Michael A. A. McGuire, Ercan Cakmak, Raphael P. Hermann
Summary: Antimony oxides are important for catalysis and flame-retardant applications. Although the lattice dynamics properties of alpha-Sb2O3 and beta-Sb2O3 have been extensively studied, their anharmonicity and low-temperature structural information have not been directly investigated. In this study, we report the powder neutron diffraction data and structural information of both phases, revealing a small region of zero thermal expansion in beta-Sb2O3 along the c axis and a deviation in atomic displacement parameters in alpha-Sb2O3. These findings provide valuable insights for further investigations.
Article
Materials Science, Multidisciplinary
Andrew F. May, Eleanor M. Clements, Heda Zhang, Raphael P. Hermann, Jiaqiang Yan, Michael A. McGuire
Summary: EuCuP and EuCuAs were studied to investigate their magnetic phase transitions and magnetoelastic coupling. EuCuP exhibited two closely spaced features in thermal expansion and specific heat capacity around the Curie temperature, possibly indicating a cascading magnetic transition or an electronic transition closely coupled to the magnetic ordering. Stronger zero-field magnetoelastic coupling was observed in EuCuP compared to EuCuAs, which was attributed to the dominant ferromagnetic interaction in EuCuP and antiferromagnetic order in EuCuAs. Anisotropic thermal expansion and strong ferromagnetic correlations were observed in EuCuAs above T-N. Both compounds showed similar electrical and thermoelectric transport behaviors, suggesting intrinsic defects and potential for achieving narrow-gap semiconducting or semimetallic behavior with defect tuning.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Michael A. McGuire, Heda Zhang, Andrew F. May, Satoshi Okamoto, Robert G. Moore, Xiaoping Wang, Clement Girod, Sean M. Thomas, Filip Ronning, Jiaqiang Yan
Summary: Alloying indium into SnBi2Te4 induces bulk superconductivity with critical temperatures up to 1.85 K and upper critical fields up to about 14 kOe. This is confirmed by electrical and thermal measurements, and the presence of a superconducting gap near 0.25 meV is suggested. The superconductivity is type-II and the existence of topological surface states has been verified. The analogy with MnBi2Te4 motivates further interest in this family of compounds, which have potential for the study of topological superconductivity.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Physical
Rahul Rao, Ryan Selhorst, Jie Jiang, Benjamin S. Conner, Ryan Siebenaller, Emmanuel Rowe, Andrea N. Giordano, Ruth Pachter, Michael A. Susner
Summary: CuInP2S6 is a novel layered ferroelectric material with a Curie temperature above room temperature. It forms self-assembled heterostructures of CIPS and IPS within the same single crystal when synthesized with Cu deficiencies. The segregation of the material into CIPS and IPS phases results in significant strains between them. The strains were measured through Raman, infrared, and optical reflectance spectra, and unique vibrational modes were identified using density functional theory calculations.
CHEMISTRY OF MATERIALS
(2023)
Article
Multidisciplinary Sciences
Yuguang Pu, Duncan Moseley, Zhen He, Krishna Chaitanya Pitike, Michael E. Manley, Jiaqiang Yan, Valentino R. Cooper, Valerie Mitchell, Vanessa K. Peterson, Bernt Johannessen, Raphael P. Hermann, Peng Cao
Summary: Researchers have developed a bottom-up method for synthesizing rocksalt high-entropy oxides (HEOs) containing Mn and Fe. They investigated the crystal structure and random cation-site occupancy of FeO-HEO, showing improved structural robustness and the viability of an oxygen sublattice as a buffer layer. Compositional analysis revealed the valence and spin state of the iron species, and the antiferromagnetic order of FeO-HEO below a transition temperature around 218 K was reported, along with predictions for the phase stability conditions of Mn and Fe-containing HEOs.
Article
Engineering, Electrical & Electronic
Sabine M. Neumayer, Anton Ievlev, Alexander Tselev, Sergey A. Basun, Benjamin S. Conner, Michael A. Susner, Petro Maksymovych
Summary: This research demonstrates the volatile ferroelectric switching of Sn2P2S6 at room temperature and reveals the strong influence of initial polarization orientation on the switching properties. The existence and mechanism of domain walls can control the shape of the hysteresis loop, enabling controlled volatile ferroelectric switching.
NEUROMORPHIC COMPUTING AND ENGINEERING
(2023)
