New Horizons for Ferroelectrics

2021 ◽  
Vol 30 (9) ◽  
pp. 24-30
Author(s):  
Chan-Ho YANG
Keyword(s):  
Lattice Defects ◽  
Fundamental Physics ◽  
New Horizons ◽  
Nanoscale Characterization ◽  
Physics Problems

Since the discovery of ferroelectricity in 1920, dielectric research has provided a variety of fundamental physics problems and sustainable applications. Advances in synthesis and nanoscale characterization, along with theoretical innovations, have made ferroelectrics more versatile. In this perspective, we discuss several directions for future ferroelectric research in terms of flexoelectricity, ferroelectric topology, and lattice defects, as well as cooperation with associated fields.

New Horizons of Predictability in Complex Dynamical Systems: From Fundamental Physics to Climate and Society

2021 ◽  
Author(s):  
Rui A. P. Perdigão
Keyword(s):  
Complex Systems ◽  
Stochastic Dynamic ◽  
Earth System ◽  
Fundamental Physics ◽  
Linear Dynamics ◽  
New Horizons ◽  
Intelligence System ◽  
Consistent Manner ◽  
Dynamic Resonance ◽  
Climate And Society

Discerning the dynamics of complex systems in a mathematically rigorous and physically consistent manner is as fascinating as intimidating of a challenge, stirring deeply and intrinsically with the most fundamental Physics, while at the same time percolating through the deepest meanders of quotidian life. The socio-natural coevolution in climate dynamics is an example of that, exhibiting a striking articulation between governing principles and free will, in a stochastic-dynamic resonance that goes way beyond a reductionist dichotomy between cosmos and chaos. Subjacent to the conceptual and operational interdisciplinarity of that challenge, lies the simple formal elegance of a lingua franca for communication with Nature. This emerges from the innermost mathematical core of the Physics of Coevolutionary Complex Systems, articulating the wealth of insights and flavours from frontier natural, social and technical sciences in a coherent, integrated manner. Communicating thus with Nature, we equip ourselves with formal tools to better appreciate and discern complexity, by deciphering a synergistic codex underlying its emergence and dynamics. Thereby opening new pathways to see the “invisible” and predict the “unpredictable” – including relative to emergent non-recurrent phenomena such as irreversible transformations and extreme geophysical events in a changing climate. Frontier advances will be shared pertaining a dynamic that translates not only the formal, aesthetical and functional beauty of the Physics of Coevolutionary Complex Systems, but also enables and capacitates the analysis, modelling and decision support in crucial matters for the environment and society. By taking our emerging Physics in an optic of operational empowerment, some of our pioneering advances will be addressed such as the intelligence system Earth System Dynamic Intelligence and the Meteoceanics QITES Constellation, at the interface between frontier non-linear dynamics and emerging quantum technologies, to take the pulse of our planet, including in the detection and early warning of extreme geophysical events from Space.

Contrast in Scanning Images of Thin Crystals

1972 ◽  
Vol 30 ◽  
pp. 520-521
Author(s):  
S. Kimoto ◽  
H. Hashimoto ◽  
S. Takashima ◽  
R. M. Stern ◽  
T. Ichinokawa
Keyword(s):  
Crystal Surface ◽  
Solid Angle ◽  
Incident Angle ◽  
Intensity Variation ◽  
Lattice Defects ◽  
Scanning Microscope ◽  
Electron Detector ◽  
Backscattered Electrons ◽  
Electron Image ◽  
Backscattered Electron

The most well known application of the scanning microscope to the crystals is known as Coates pattern. The contrast of this image depends on the variation of the incident angle of the beam to the crystal surface. The defect in the crystal surface causes to make contrast in normal scanning image with constant incident angle. The intensity variation of the backscattered electrons in the scanning microscopy was calculated for the defect in the crystals by Clarke and Howie. Clarke also observed the defect using a scanning microscope.This paper reports the observation of lattice defects appears in thin crystals through backscattered, secondary and transmitted electron image. As a backscattered electron detector, a p-n junction detector of 0.9 π solid angle has been prepared for JSM-50A. The gain of the detector itself is 1.2 x 104 at 50 kV and the gain of additional AC amplifier using band width 100 Hz ∼ 10 kHz is 106.

Crystal structure-size relationship in ultrafine metallic particles

1989 ◽  
Vol 47 ◽  
pp. 266-267
Author(s):  
Jun Liu ◽  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Ultrafine Particles ◽  
Carbon Film ◽  
Lattice Defects ◽  
Careful Examination ◽  
Seeded Growth ◽  
Gold Particles ◽  
Metallic Particles ◽  
Interfacial Structures ◽  
Typical Particle ◽  
Many Particles

Ultrafine particles usually have unique physical properties. This study illustrates how the lattice defects and interfacial structures between particles are related to the size of ultrafine crystalline gold particles.Colloidal gold particles were produced by reducing gold chloride with sodium citrate at 100°C. In this process, particle size can be controlled by changing the concentration of the reactant. TEM samples are prepared by transferring a small amount of solution onto a thin (5 nm) carbon film which is suspended on a copper grid. In this work, all experiments were performed with Philips 430T at 300 kV.With controlled seeded growth, particles of different sizes are produced, as shown in Figure 1. By a careful examination, it can be resolved that very small particles have lattice defects with complex interfaces. Some typical particle structures include multiple twins, resulting in a five-fold symmetry bicrystals, and highly disordered regions. Many particles are too complex to be described by simple models.

Physics Expertise and the Perception of Physics Problems

1992 ◽  
Author(s):  
Roger W. Schvaneveldt ◽  
David R. Euston ◽  
David S. Sward ◽  
Alan Van Heuvelen
Keyword(s):  
Physics Problems
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