Read by QxMD icon Read


Dawei Li, Zhiyong Xiao, Sai Mu, Fei Wang, Ying Liu, Jingfeng Song, Xi Huang, Lijia Jiang, Jun Xiao, Lei Liu, Stephen Ducharme, Bai Cui, Xia Hong, Lan Jiang, Jean-Francois Silvain, Yongfeng Lu
Single-crystal transition metal dichalcogenides (TMDs) and TMD-based hetero-junctions have recently attracted significant research and industrial interest owing to their intriguing optical and electrical properties. However, the lack of a simple, low-cost, environmentally friendly, synthetic method and a poor understanding of the growth mechanism post a huge challenge to implementing TMDs in practical applications. In this work, we developed a novel approach for direct formation of high-quality, monolayer and few-layer MoS2 single crystal domains via a single-step rapid thermal processing of a sandwiched reactor with sulfur and molybdenum (Mo) film in a confined reaction space...
January 19, 2018: Nano Letters
Shekhar Tyagi, Gaurav Sharma, Vasant G Sathe
The competition and cooperation between ferroelectric and antiferrodistortive (AFD) instabilities are studied using pressure dependent Raman spectroscopy on polycrystalline powder samples of Sr1-xCaxTiO3(x=0.0, 0.06, 0.25, 0.35). For x=0.0 composition, broad polar mode is detected in the Raman spectra above 6 GPa, while for x=0.06 composition the polar modes appear well above 9 GPa where the AFD modes showed strong suppression. In x=0.25 and 0.35 composition the application of small pressure results in appearance of strong AFD modes suppressing the polar modes...
January 19, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
Peter Keil, Maximilian Trapp, Nikola Novak, Till Frömling, Hans-Joachim Kleebe, Jürgen Rödel
Coupling of magnetic, ferroelectric, or piezoelectric properties with charge transport at oxide interfaces provides the option to revolutionize classical electronics. Here, the modulation of electrostatic potential barriers at tailored ZnO bicrystal interfaces by stress-induced piezoelectric polarization is reported. Specimen design by epitaxial solid-state transformation allows for both optimal polarization vector alignment and tailoring of defect states at a semiconductor-semiconductor interface. Both quantities are probed by transmission electron microscopy...
January 19, 2018: Advanced Materials
Zhengyu Feng, A D L Chandani Perera, Atsuo Fukuda, Jagdish K Vij, Ken Ishikawa, Atsuo Iida, Yoichi Takanishi
A mixture of two selenium-containing compounds, 80 wt. % AS657 and 20 wt. % AS620, are studied with two complementary methods, electric-field-induced birefringence (EFIB) and microbeam resonant x-ray scattering (μRXS). The mixture shows the typical phase sequence of Sm-C_{A}^{*}-1/3-1/2-Sm-C^{*}-Sm-C_{α}^{*}-Sm-A, where 1/3 and 1/2 are two prototypal ferrielectric and antiferroelectric subphases with three- and four-layer unit cells, respectively. Here we designate the subphase as its q_{T} number defined by the ratio of [F]/([F]+[A]), where [F] and [A] are the numbers of synclinic ferroelectric and anticlinic antiferroelectric orderings in the unit cell, respectively...
July 2017: Physical Review. E
Tim Verhagen, Vaclav Vales, Martin Kalbac, Jana Vejpravova
Graphene is extremely sensitive to optical, electrical and mechanical stimuli, which cause a significant variation of the band structure, thus physiochemical properties. In our work, we report on changes of strain and doping in graphene grown by chemical vapor deposition (CVD) and transferred onto a BaTiO3(100) (BTO) single-crystal. The BTO is known as a ferroelectric material, which undergoes several thermoelastic martensitic phase transitions when it is cooled from 300 K to 10K. In order to enhance the very weak Raman signal of the graphene monolayer (ML) on the BTO, a 15 nm thin gold layer was deposited on top of the graphene ML to benefit from the surface enhanced Raman scattering (SERS)...
January 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
Xian-Zhu Deng, Chuang Song, Yin-Lin Tong, Guoliang Yuan, Feng Gao, Dan-Qing Liu, Shan-Tao Zhang
As one of the most promising photocatalysts, graphitic carbon nitride (g-C3N4) shows a visible light response and great chemical stability. However, its relatively low photocatalytic efficiency is a major obstacle to actual applications. Here an effective and feasible method to dramatically increase the visible light photocatalytic efficiency by forming C3N4/BiFeO3 ferroelectric heterojunctions is reported, wherein the band alignment and piezo-/ferroelectricity have synergistic positive effects in accelerating the separation of the photogenerated carriers...
January 17, 2018: Physical Chemistry Chemical Physics: PCCP
Xudong Wang, Yan Chen, Guangjian Wu, Jianlu Wang, Bobo Tian, Shuo Sun, Hong Shen, Tie Lin, Wei-Da Hu, Tingting Kang, Minghua Tang, Yongguang Xiao, Jinglan Sun, Xiangjian Meng, Junhao Chu
Graphene has received numerous attention for future nanoelectronics and optoelectronics. The Dirac point is a key parameter of graphene that provides information about its carrier properties. There are lots of methods to tune the Dirac point of graphene, such as chemical doping, impurities, defects, and disorder. In this study, we report a different approach to tune the Dirac point of graphene using a ferroelectric polarization field. The Dirac point can be adjusted to near the ferroelectric coercive voltage regardless its original position...
January 17, 2018: Nanotechnology
Padraic Shafer, Pablo García-Fernández, Pablo Aguado-Puente, Anoop R Damodaran, Ajay K Yadav, Christopher T Nelson, Shang-Lin Hsu, Jacek C Wojdeł, Jorge Íñiguez, Lane W Martin, Elke Arenholz, Javier Junquera, Ramamoorthy Ramesh
Chirality is a geometrical property by which an object is not superimposable onto its mirror image, thereby imparting a handedness. Chirality determines many important properties in nature-from the strength of the weak interactions according to the electroweak theory in particle physics to the binding of enzymes with naturally occurring amino acids or sugars, reactions that are fundamental for life. In condensed matter physics, the prediction of topologically protected magnetic skyrmions and related spin textures in chiral magnets has stimulated significant research...
January 16, 2018: Proceedings of the National Academy of Sciences of the United States of America
Zongyao Li, Yujin Cho, Xiang Li, Xinyu Li, Akihisa Aimi, Yoshiyuki Inaguma, Jose Antonio Alonso, Maria Teresa Fernandez-Diaz, Jiaqiang Yan, Michael C Downer, Graeme Henkelman, John B Goodenough, Jianshi Zhou
Perovskite oxides hosting ferroelectricity are particularly important materials for modern technologies. The ferroelectric transition in the well-known oxides BaTiO3 and PbTiO3 is realized by softening of a vibration mode in the cubic perovskite structure. For most perovskite oxides, octahedral-site tilting systems are developed to accommodate the bonding mismatch due to a geometric tolerance factor t = (A-O)/[√2(B-O)] < 1. In the absence of cations having lone-pair electrons, e.g. Bi3+ and Pb2+, all simple and complex A-site and B-site ordered perovskite oxides with a t < 1 show a variety of tilting systems and none of them become ferroelectric...
January 15, 2018: Journal of the American Chemical Society
Rohit Saraf, Long Pu, Vivek Maheshwari
Organolead trihalide perovskite MAPbI3 shows a distinctive combination of properties such as being ferroelectric and semiconducting, with ion migration effects under poling by electric fields. The combination of its ferroelectric and semiconducting nature is used to make a light harvesting, self-powered tactile sensor. This sensor interfaces ZnO nanosheets as a pressure-sensitive drain on the MAPbI3 film and once poled is operational for at least 72 h with just light illumination. The sensor is monolithic in structure, has linear response till 76 kPa, and is able to operate continuously as the energy harvesting mechanism is decoupled from its pressure sensing mechanism...
January 15, 2018: Advanced Materials
Carsten Richter, Matthias Zschornak, Dmitri Novikov, Erik Mehner, Melanie Nentwich, Juliane Hanzig, Semën Gorfman, Dirk C Meyer
Physical properties of crystalline materials often manifest themselves as atomic displacements either away from symmetry positions or driven by external fields. Especially the origin of multiferroic or magnetoelectric effects may be hard to ascertain as the related displacements can reach the detection limit. Here we present a resonant X-ray crystal structure analysis technique that shows enhanced sensitivity to minute atomic displacements. It is applied to a recently found crystalline modification of strontium titanate that forms in single crystals under electric field due to oxygen vacancy migration...
January 12, 2018: Nature Communications
Xiaodong Jian, Biao Lu, Dandan Li, Yingbang Yao, Tao Tao, Bo Liang, Jin-Hong Guo, Yi-Jiang Zeng, Jia-Le Chen, Sheng-Guo Lu
Barium zirconate titanate (Ba(ZrxTi1-x)O3-BZT) ceramics with Zr4+ content x of 5, 10, 15, 20, 25 and 30 mol%, were prepared using a solid-state-reaction approach. The microstructures, morphologies, and electric properties were characterized using XRD, SEM and impedance analysis methods, respectively. The dielectric analyses indicate that the BZT bulk ceramics show characteristics of phase transition from a normal ferroelectric to a relaxor ferroelectric with the increasing Zr4+ ionic content. The electrocaloric effect (ECE) adiabatic temperature change decreases with the increasing Zr4+ content...
January 12, 2018: ACS Applied Materials & Interfaces
Rokyeon Kim, Jaejun Yu, Hosub Jin
Topological electronics is a new field that uses topological charges as current-carrying degrees of freedom. For topological electronics applications, systems should host topologically distinct phases to control the topological domain boundary through which the topological charges can flow. Due to their multiple Dirac cones and the π-Berry phase of each Dirac cone, graphene-like electronic structures constitute an ideal platform for topological electronics; graphene can provide various topological phases when incorporated with large spin-orbit coupling and mass-gap tunability via symmetry-breaking...
January 11, 2018: Scientific Reports
Markus Kratzer, Michael Lasnik, Sören Röhrig, Christian Teichert, Marco Deluca
Lead zirconate titanate (PZT) is one of the prominent materials used in polycrystalline piezoelectric devices. Since the ferroelectric domain orientation is the most important parameter affecting the electromechanical performance, analyzing the domain orientation distribution is of great importance for the development and understanding of improved piezoceramic devices. Here, vector piezoresponse force microscopy (vector-PFM) has been applied in order to reconstruct the ferroelectric domain orientation distribution function of polished sections of device-ready polycrystalline lead zirconate titanate (PZT) material...
January 11, 2018: Scientific Reports
Jike Lyu, Ignasi Fina, Raul Solanas, Josep Fontcuberta, Florencio Sánchez
Ferroelectric BaTiO3 films with large polarization have been integrated with Si(001) by pulsed laser deposition. High quality c-oriented epitaxial films are obtained in a substrate temperature range of about 300 °C wide. The deposition temperature critically affects the growth kinetics and thermodynamics balance, resulting on a high impact in the strain of the BaTiO3 polar axis, which can exceed 2% in films thicker than 100 nm. The ferroelectric polarization scales with the strain and therefore deposition temperature can be used as an efficient tool to tailor ferroelectric polarization...
January 11, 2018: Scientific Reports
Li Yin, Xiaocha Wang, Wenbo Mi
The generation and modulation on valley and spin degrees of freedom are essential to multifunctional electronic devices. Herewith, the electronic structures in BiXO3/BiIrO3 (X=Fe, Mn) ferroelectric superlattices are studied by first-principles calculations with spin-orbital coupling. Different from previous BiAlO3/BiIrO3 system, both valley and spin polarizations in bilayered BiIrO3 are achieved in BiXO3/BiIrO3 superlattices, where the spin polarization in the valley can be engineered by the spin orientation of Fe or Mn owing to the xy-plane orbitals...
January 11, 2018: ACS Applied Materials & Interfaces
Tian-Fu Zhang, Xian-Xiong Huang, Xin-Gui Tang, Yan-Ping Jiang, Qiu-Xiang Liu, Biao Lu, Sheng-Guo Lu
The unique properties and great variety of relaxer ferroelectrics make them highly attractive in energy-storage and solid-state refrigeration technologies. In this work, lanthanum modified lead titanate ceramics are prepared and studied. The giant electrocaloric effect in lanthanum modified lead titanate ceramics is revealed for the first time. Large refrigeration efficiency (27.4) and high adiabatic temperature change (1.67 K) are achieved by indirect analysis. Direct measurements of electrocaloric effect show that reversible adiabatic temperature change is also about 1...
January 10, 2018: Scientific Reports
C Ye, J B Wang, B Li, X L Zhong
Electrocaloric effect (ECE) has the potential applications in solid-state refrigeration with the features of high efficiency and environmentally friendly. Large adiabatic temperature change in a wide temperature range is needed for electrocaloric effect to meet the requirement of commercially application. In this work, giant electrocaloric effect is found in PbTiO3 nanoparticle with double-vortex domain structure in a wide temperature range by using phase field method, which the lowest and highest adiabatic temperature change (ΔT) is 7...
January 10, 2018: Scientific Reports
Giuseppe Nasti, Sara Coppola, Federico Olivieri, Veronica Vespini, Vito Pagliarulo, Pietro Ferraro
Electrophoresis (EP) and dielectrophoresis (DEP) are two well established methodologies to manipulate nanoparticles (NPs). Recently, a DEP by virtual electrodes platform was demonstrated on ferroelectric substrates where the driving force is due to the strong electric field generated by pyroelectric effect thus opening new scenarios for manipulating the matter. Such innovative approach named pyroelectric-DEP has several advantages over the traditional EP and DEP. However, a detailed study on this novel approach is required for understanding the complex pathways traced by nanoparticles (NP) under the action of the pyroelectric driven forces and thus for explaining the final patterns...
January 10, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Yudong Liu, Junmeng Guo, Aifang Yu, Yang Zhang, Jinzong Kou, Ke Zhang, Rongmei Wen, Yan Zhang, Junyi Zhai, Zhong Lin Wang
Utilizing magnetic field directly modulating/turning the charge carrier transport behavior of field-effect transistor (FET) at ambient conditions is an enormous challenge in the field of micro-nanoelectronics. Here, a new type of magnetic-induced-piezopotential gated field-effect-transistor (MIPG-FET) base on laminate composites is proposed, which consists of Terfenol-D, a ferroelectric single crystal (PMNPT), and MoS2 flake. When applying an external magnetic field to the MIPG-FET, the piezopotential of PMNPT triggered by magnetostriction of the Terfenol-D can serve as the gate voltage to effectively modulate/control the carrier transport process and the corresponding drain current at room temperature...
January 10, 2018: Advanced Materials
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"