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1.
Dynamic generation of plasmonic Moiré fringes using a phase engineered optical vortex (OV) beam is experimentally demonstrated. Owing to the unique helical phase carried by an OV beam, the initial phase of surface plasmon polaritons (SPPs) emanating from a metallic grating can be adjusted dynamically by changing the phase hologram displayed on a spatial light modulator. Plasmonic Moiré fringes are readily achieved by overlapping two SPP standing waves with certain angular misalignment, excited by the positive and negative topological charge components, respectively, of a cogwheel-like OV beam. The near-field scanning optical microscopy measurement result of SPP distributions has shown a good agreement with the numerical predictions. 相似文献
2.
The number of least degrees of freedom required for a polarization controller to transform any state of polarization to any other output covering the entire Poincaré sphere 下载免费PDF全文
Using two typical types of polarization controller, this paper
analyses theoretically and experimentally the fact that it is
necessary to adjust at least three instead of two waveplates in
order to transform any state of polarization to any other output
covering the entire Poincar\'{e} sphere. The experimental results
are exactly in accordance with the theory discussed in this paper.
It has corrected the conventional and inaccurate point of view that
two waveplates of a polarization controller are adequate to complete
the transformation of state of polarization. 相似文献
3.
An algebraic approach to Kepler problem in a curved space is introduced. By using this approach, the creation and annihilation operators associated to this system and their algebra are calculated. These operators satisfy a deformed Weyl–Heisenberg algebra which can be assumed as a deformed su(2) algebra. By using this fact, the nonlinear coherent states of this system are constructed. The scalar product and Bargmann representation of this family of nonlinear coherent states are constructed. The present contribution shows that these nonlinear coherent states possess some non-classical features which strongly depend on the Kepler coupling constant and space curvature. Depending on the non-classical measures, the smaller the curvature parameter, the more the non-classical features. Moreover, the stronger Kepler constant provides more non-classical features. 相似文献
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We propose theoretically and verify experimentally a compact optical configuration to directly generate arbitrary vector vortex beams on a hybrid-order Poincaré sphere with good flexibility and high efficiency based on a reflective phase-only liquid crystal spatial light modulator(LC-SLM). The conversion system, consisting of an LC-SLM and a quarter-wave plate, can be considered a flexible dielectric metasurface to simultaneously modulate inhomogeneous polarization and helical phase-front. This approach has some advantages, including a simple experimental setup, good flexibility, and high efficiency. Orthogonally polarized modes alignment and an explicit superposition existing in the conventional method are not necessary in the proposed method, which exhibits potential applications in many advanced domains. 相似文献
6.
Although reflective bistable twisted nematic (RBTN) displays have potential in low-power-consumption applications, to achieve the optimum conditions for both bistable states simultaneously remains a challenge. We use a geometrical method based on the Poincaré sphere representation to obtain the optimum conditions that can simultaneously satisfy both bistable states for a RBTN structure. With this method, the optimum conditions can be obtained analytically and the operation modes can be clearly visualized and better understood. 相似文献
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A higher-order Poincaré sphere and Stokes parameter representation of the higher-order states of polarization of vector vortex beams that includes radial and azimuthal polarized cylindrical vector beams is presented. The higher-order Poincaré sphere is constructed by naturally extending the Jones vector basis of plane wave polarization in terms of optical spin angular momentum to the total optical angular momentum that includes higher dimensional orbital angular momentum. The salient properties of this representation are illustrated by its ability to describe the higher-order modes of optical fiber waveguides, more exotic vector beams, and a higher-order Pancharatnam-Berry geometric phase. 相似文献
9.
J. Zhu F.-K. Li 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,80(1):83-87
A theoretical study based on discrete dipole approximation (DDA) and
coupling effect is presented on the tunable transverse surface plasmon
resonance (SPR) in a gold nanotube with varying aspect ratio (AR). Because
gold nanotube has the shape features from both rod and shell, both the AR
and wall thickness can greatly affect the transverse SPR. It is observed
that the maximum red shift can be obtained with small wall thickness and AR.
By calculating the local field distribution, the physical mechanism of this
multi shape factors controlled plasmon shifting has been illustrated by the
coulombic interaction from the charges at the interfaces of gold nanotube.
This study indicates that finding the surface charge distribution by
calculating the local electric field can be used as an effective method to
analyze the plasmonic characters in complicated metallic nanostructure. 相似文献
10.
A pair of negative-poles in microelectroremoval process is a precision nanoscale production of a reclaim system of ITO nanostructure (ITO) removal from optoelectronic flat panel displays’ color filter surface is demonstrated in the current study. The microelectroremoval just needs quite short time to make the ITO remove easily and cleanly. In the current experiment, the pair of negative-poles constructs a high efficiency in ITO removal and takes less time for the same amount of ITO removal compared with a single negative-pole. A small size of the negative-poles and a small gap-width between the negative-poles and the ITO surface takes less time for the ITO removal. Pulsed direct current is advantageous to associate with the fast feed rate of workpiece. A high rotational speed of the negative-poles or a higher concentration of the electrolyte corresponds to a higher removal rate for ITO. A fast feed rate of the displays’ color filters combined with enough electric power produces fast ITO removal. Through the ultra-precise removal of thin-film nanostructure, the optoelectronic semiconductor industry can effectively reclaim defective products, reducing production costs. 相似文献
11.
Masaaki Nakamura Satoshi Nishimoto 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(9):203
We discuss the exact plaquette-ordered ground states of the generalized Hubbard model on the Kagomé lattice for several fillings, by constructing the Hamiltonian as a sum of products of projection operators for up and down spin sectors. The obtained exact ground states are interpreted as Néel ordered states on the bond-located electrons. We determine several parameter regions of the exact ground states, and calculate the entanglement entropy. We examine the above results by numerical calculations based on exact diagonalization and density-matrix renormalization group methods. 相似文献
12.
A 50 cm silver coated hollow fiber with inner diameter of 250 μm and filled with argon has been used to compress optical pulses
from a Ti:sapphire laser at 800 nm. Input pulses with energy of 250 μJ and duration of 110 fs were used and compressed pulses
with energy of 220 μJ and duration of 20 fs were generated by using a prism compressor. Numerical and experimental results
are compared. There is good agreement between the measured beam diameters of the hollow-fiber output pulse and the calculated
values obtained from propagation of the HE11 mode into free space. For comparison, a similar uncoated fused-silica hollow fiber was also used to obtain 20 fs compressed
pulses with an energy of 190 μJ.
Received: 7 September 2002 / Published online: 26 March 2003
RID="*"
ID="*"Corresponding author. Fax: +1-780/492-1811, E-mail: mohebbi@ee.ualberta.ca 相似文献
13.
Jack P. Sleigh David P. McMahon Alessandro Troisi 《Applied Physics A: Materials Science & Processing》2009,95(1):147-152
The thermal fluctuation of the intermolecular hopping integral in the series of polyacene crystals (naphthalene, anthracene,
tetracene, pentacene) was evaluated computationally using a combined molecular dynamics and quantum chemistry approach. It
was shown that these large fluctuations can manifest themselves in a temperature-dependent relatively broad tail of the density
of states extending from the valence band into the gap. It was also shown that this tail accounts for a large fraction of
all states in the valence band and therefore it may be essential for accurately describing the charge transport and optical
properties. 相似文献
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F. Amrani A. Haboucha M. Salhi H. Leblond A. Komarov F. Sanchez 《Applied physics. B, Lasers and optics》2010,99(1-2):107-114
We investigate experimentally ordered and disordered pattern formation of solitons in a double-clad fiber laser. We point out an analogy between the different states of matter and the states of a set of dissipative solitons. In particular, we have identified a gas, a supersonic gas flow, a liquid, a polycrystal and a crystal of solitons. The different states are obtained only by adjustment of the intracavity phase plates. 相似文献
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V. S. Anishchenko M. Khairulin G. Strelkova J. Kurths 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,82(3-4):219-225
Characteristics of the Poincaré return times are considered in a one-dimensional cubic map with a chaotic nonhyperbolic attractor. Two approaches, local one (Kac’s theorem) and global one related with the AP-dimension estimation of return times, are used. The return times characteristics are studied in the presence of external noise. The characteristics of Poincaré recurrences are compared with the form of probability measure and the complete correspondence of the obtained results with the mathematical theory is shown. The influence of the attractor crisis on the return time characteristics is also analyzed. The obtained results have a methodical and educational significance and can be used for solving a number of applied tasks. 相似文献
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The thermodynamic properties of a cluster of point Coulomb charges on a sphere have been analyzed using the Monte Carlo method
for the number of charges 20 ≤ N ≤ 90. The ground state of the system of charges is described in the model of a closed quasi-two-dimensional triangular lattice
with topological defects. We have determined the dependence of the Lindeman parameter δL of this system on N and on the dimensionless parameter $
\tilde T
$
\tilde T
, which is proportional to the temperature T and to the radius R of the cluster: $
\tilde T = {{k_B T\varepsilon R} \mathord{\left/
{\vphantom {{k_B T\varepsilon R} {e^2 }}} \right.
\kern-\nulldelimiterspace} {e^2 }}
$
\tilde T = {{k_B T\varepsilon R} \mathord{\left/
{\vphantom {{k_B T\varepsilon R} {e^2 }}} \right.
\kern-\nulldelimiterspace} {e^2 }}
, where ∈ is the dielectric constant of the medium and e is the charge of a particle. The “magic numbers,” i.e., the N values, for which the melting point of the closed triangular lattice of charges is much higher than those for neighboring
N values, have been found. The evolution of the lattice-melting mechanisms with an increase in the number of charges N in a mesoscopic cluster has been analyzed. For N ≤ 32, the melting of the lattice does not involve dislocations (nontopological melting); this behavior of the mesoscopic
system of charges on the sphere differs from the behavior of the extended planar two-dimensional system. At N ≳ 50, melting is accompanied by the formation of dislocations. The mechanism of dislocation-free non-topological melting
of a closed lattice, which occurs at small N values and is associated with the cooperative rotational motion of “rings” of particles, has been analyzed. The model has
various implementations in the mesoscopic region; in particular, it describes the system of electrons over the liquid-helium
cluster, the liquid-helium cluster with incorporated charged particles, a multielectron bubble in liquid helium, a charged
quantum dot, etc. 相似文献