Critical point energy as a function of electric field determined by electroreflectance of surface-intrinsic-n+ type doped GaAs

2004 ◽  
Vol 85 (18) ◽  
pp. 4064-4066 ◽  
Author(s):  
Y. S. Chen ◽  
K. S. Wu ◽  
D. P. Wang ◽  
K. F. Huang ◽  
T. C. Huang
Keyword(s):  
Electric Field ◽  
Critical Point ◽  
Point Energy

Electric field induced phase transition in first order ferroelectrics with large zero point energy

2008 ◽  
Vol 387 (1) ◽  
pp. 115-122 ◽  
Author(s):  
C.L. Wang ◽  
J.C. Li ◽  
M.L. Zhao ◽  
J.L. Zhang ◽  
W.L. Zhong ◽  
...  
Keyword(s):  
Phase Transition ◽  
Electric Field ◽  
Zero Point ◽  
Zero Point Energy ◽  
Point Energy ◽  
First Order

Electric-field-induced structure in polymer solutions near the critical point

1992 ◽  
Vol 25 (26) ◽  
pp. 7234-7246 ◽  
Author(s):  
Denis Wirtz ◽  
Klaus Berend ◽  
Gerald G. Fuller
Keyword(s):  
Electric Field ◽  
Critical Point ◽  
Polymer Solutions ◽  
Induced Structure

scholarly journals DC field microscopy of Rydberg Li atoms

2016 ◽  
Vol 94 (6) ◽  
pp. 548-557 ◽  
Author(s):  
Dehua Wang ◽  
Shaohao Cheng ◽  
Qiang Chen ◽  
Zhaohang Chen
Keyword(s):  
Electric Field ◽  
Semiclassical Approximation ◽  
Field Potential ◽  
Detector Plane ◽  
Point Energy ◽  
Atomic Core ◽  
Density Distributions ◽  
Scattering Effect ◽  
Electric Field Potential ◽  
Probability Density Distributions

The DC field microscopy of Rydberg Li atoms has been studied on the basis of the semiclassical theory for the first time. In particular, we discuss the atomic core scattering effect in the ionization dynamics of the Rydberg Li atom. Unlike the case of the photoionization of a Rydberg H atom in an electric field, where the photoionization microscopy interference patterns are mainly caused by the Coulomb scattering and the electric field potential, for the photoionization of a Rydberg Li atom in an electric field, the influence of the atomic core scattering effect on the photoionization microscopy interference patterns plays an important role. In addition, the structure of the interference pattern, which contains the spatial component of the electronic wave function, evolves smoothly with the electron energy above the saddle point energy. The observed oscillatory patterns in the electron probability density distributions on the detector plane are interpreted within the framework of the semiclassical approximation, which can be considered as a manifestation of interference between various electron trajectories arriving at a given point from the atom to the detector plane. This study provides some reference values for future experimental research on photoionization microscopy of the non-hydrogen Rydberg atoms in the presence of external fields.

Determination of the Tb A4-critical point energy from angle-resolved UV photoemission of Tb(0001)

1991 ◽  
Vol 3 (32) ◽  
pp. 6165-6168 ◽  
Author(s):  
R I R Blyth ◽  
S S Dhesi ◽  
A J Patchett ◽  
T Mitrelias ◽  
N P Prince ◽  
...  
Keyword(s):  
Critical Point ◽  
Point Energy

Computer modeling and molecular dynamics of polarization switching in the ferroelectric films PVDF and P(VDF-TrFE) on nanoscale

2015 ◽  
Vol 10 (1) ◽  
pp. 131-153 ◽  
Author(s):  
В.Е. Геворкян ◽  
V.E. Gevorkyan
Keyword(s):  
Molecular Dynamics ◽  
Electric Field ◽  
Total Energy ◽  
Critical Point ◽  
Quantum Chemical ◽  
Polarization Switching ◽  
Total System ◽  
Switching Mechanism ◽  
Gradual Shift ◽  
Semi Empirical

In this paper, molecular models are used to investigate and analyze the structure and polarization of polyvinylidene fluoride (PVDF) and poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) Langmuir-Blodgett (LB) nanofilms, depending on the structure and composition of the monomers of their polymer and copolymer chains. Quantum-mechanical calculations and modeling, as well as molecular dynamics (MD) simulations based on semi-empirical quantum-chemical methods (such as PM3), show that the energy of the studied PVDF and P (VDF-TrFE) molecular structures, and their polarization switching proceed by homogeneous switching mechanism in the framework of the phenomenological theory of Landau-Ginzburg-Devonshire (LGD) in the linear approximation of low values of the electric field. The magnitude of the resulting critical coercive field is within the EC ~ 0.5 ... 2.0 GV/m, which is consistent with experimental data. It is also found that the uniform polarization switching mechanism of the polymer chains PVDF and P (VDF-TrFE) is due to the quantum properties of the molecular orbitals of the electron subsystem: the applied electric field induces a gradual shift of the electron "clouds" density (electron polarizability), which in turn causes a gradual shift of the nuclear cores, in accordance with the principle of minimum total energy of the system, and this leads eventually, when it reaches a critical point (bifurcation) - to overturn of the entire chain and a sharp decrease in the total energy of the total system to its energetically more favorable state. This is clearly seen in both the polarization hysteresis loops, and the total energy changes. In this case, the turnover chain time, obtained by molecular dynamics within semi-empirical quantum-chemical PM3 approach in a limited Hartree-Fock approximation, when approaching this critical point, increases sharply, tending to infinity, which corresponds to the theory of LGD.

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