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1.
基于谐振式光学陀螺高灵敏度、低成本与微型化的发展需求, 为了实现高灵敏度的谐振式微光机电陀螺, 提出了以集成光学微谐振腔领域里高Q值、大直径谐振腔的制作为目标, 应用方向为谐振式光学陀螺的球形光学微谐振腔核心敏感单元. 在实验中以氢火焰作为热源采用熔融法制备球形光学微谐振腔. 通过调节氢气的流量控制氢火焰热源面积, 制备了不同直径(300-2200 μm)的球形谐振腔, 分析了球形谐振腔Q 值、DQ乘积、陀螺灵敏度与谐振腔直径D的对应关系及其原因, 获得了最优参数的面向谐振式光学陀螺的球形谐振腔敏感单元. D=1260 μm时, 球腔品质因数 Q=7.18×107, 得到的最优陀螺灵敏度约为10°/h, 满足商业级应用的需求, 为芯片级、高精度、低成本的新型谐振式光学微腔陀螺的研究奠定了实验基础. 相似文献
2.
A general expression for the resonant contribution to a tunneling current has been obtained and analyzed in the tunneling
Hamiltonian approximation. Two types of resonant tunneling structures are considered: structures with a random impurity distribution
and double-barrier structures, where the resonant level results from size quantization. The effect of temperature on the current-voltage
curves of tunneling structures is discussed. The study of the effect of potential barrier profile on the d
2
I/dV
2 line shape is of interest for experiments in inelastic tunneling spectroscopy. Various experimental situations where the
inelastic component of the tunneling current can become comparable to the elastic one are discussed.
Fiz. Tverd. Tela (St. Petersburg) 40, 1151–1155 (June 1998) 相似文献
3.
Resonant tunneling is accompanied by the accumulation of 2D electrons in the quantum well between the barriers of resonant
tunneling diodes. In high-quality structures this gives a Z-shaped current-voltage characteristic, and it is shown that self-excitation of 2D plasmons occurs in this quantum well for
any external circuit at completely realistic parameters of the structures.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 8, 628–633 (25 October 1998) 相似文献
4.
本文主要就激光陀螺、光纤陀螺、半球谐振陀螺、石英音叉陀螺等光电惯性传感器的发展及应用进行了介绍。并对兵器行业应用和发展光学惯性器件提出建议。 相似文献
5.
I. A. Devyatov M. Yu. Kupriyanov 《Journal of Experimental and Theoretical Physics》1997,85(1):189-194
The Josephson tunneling current in S-I-S structures where the main current transport channel is resonant tunneling through
an isolated localized state is calculated using the Bogolyubov-de Gennes equations. It is shown that the efficiency of equilibrium
Josephson resonant tunneling is determined only by the ratio of the width of the resonance level to the absolute value of
the order parameter for the superconducting electrodes with arbitrary relationships among the system parameters.
Zh. éksp. Teor. Fiz. 112, 342–352 (July 1997) 相似文献
6.
Electron transmission in the two-, three-, and four-terminal nanostructures is considered under the influence of a radiation
field. The frequency of the radiation field is tuned to the transition between the energy of a bound state and the Fermi energy
of the incident electrons. The radiation induced resonant peaks and dips of the electron transport are exhibited for zero
and low magnetic fields. It is shown that rotation of the radiation field polarization can effectively control the electron
transport into different electrodes attached to the structures because of the symmetry of the structures. The resonant anomalies
of the Hall resistance are found in a weak magnetic field.
Zh. éksp. Teor. Fiz. 114, 1954–1970 (December 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
7.
Abstract The photodetachment of negative ions in a static electric field exhibits some new characteristic features and has beer considered in various theortical approaches.1 Most of them, however, neglect the short-range interaction between the escaping electron and the atomic core, and must be modified to describe various resonant effects. Experiments2 have shown very rich resonant structure in a dc-field, which can be attributed to the mixing of different excited states in the negative ion, to competition between elastic and inelastic decay channels, and to tunneling effects induced by the field. It is known that various resonant structures in Photoprocesses can be successfully described within standard multichannel quantum defect theory (MQDT). We present a modified MQDT frame transformation approach to extend the standard method to long-range potentials with nonspherical symmetry. In our treatment both the electron-field and electron-atom interactions are treated nonperturbatively and on an equal footing. The resulting theoretical calculations are compared with experimental data on field-modified H? photodetachment in the vicinity of the n = 2 resonances. 相似文献
8.
Detecting and quantifying temporal correlations in stochastic resonance via information theory measures 总被引:1,自引:0,他引:1
O. A. Rosso C. Masoller 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,69(1):37-43
We show that Information Theory quantifiers are suitable tools for detecting and for quantifying noise-induced temporal correlations
in stochastic resonance phenomena. We use the Bandt & Pompe (BP) method [Phys. Rev. Lett. 88, 174102 (2002)] to define a probability distribution, P, that fully characterizes temporal correlations. The BP method is
based on a comparison of neighboring values, and here is applied to the temporal sequence of residence-time intervals generated
by the paradigmatic model of a Brownian particle in a sinusoidally modulated bistable potential. The probability distribution
P generated via the BP method has associated a normalized Shannon entropy, H[P], and a statistical complexity measure, C[P],
which is defined as proposed by Rosso et al. [Phys. Rev. Lett. 99, 154102 (2007)]. The statistical complexity quantifies not only randomness but also the presence of correlational structures,
the two extreme circumstances of maximum knowledge (“perfect order") and maximum ignorance (“complete randomness") being regarded
an “trivial", and in consequence, having complexity C = 0. We show that both, H and C, display resonant features as a function
of the noise intensity, i.e., for an optimal level of noise the entropy displays a minimum and the complexity, a maximum.
This resonant behavior indicates noise-enhanced temporal correlations in the sequence of residence-time intervals. The methodology
proposed here has great potential for the precise detection of subtle signatures of noise-induced temporal correlations in
real-world complex signals. 相似文献
9.
10.
R. Ya. Rasulov Yu. E. Salenko T. Éski A. Tukhtamatov 《Physics of the Solid State》1998,40(7):1225-1227
The far infrared absorption spectrum caused by optical transitions of holes between size-quantization subbands is calculated
for p-GaAs/AlGaAs(001) quantum-well structures. The selection rules for optical transitions at the center of the two-dimensional
Brillouin zone are determined. Allowance is made for resonant saturation of one-photon electronic transitions between size-quantized
subbands of light and heavy holes. The linear circular dichroism in one-photon nonlinear (resonant) and two-photon absorption
of light in a size-quantized well are investigated.
Fiz. Tverd. Tela (St. Petersburg) 40, 1347–1349 (July 1998) 相似文献
11.
Optical properties and photonic bands of GaAs photonic crystal waveguides with tilted square lattice
M. Galli M. Agio L.C. Andreani L. Atzeni D. Bajoni G. Guizzetti L. Businaro E. Di Fabrizio F. Romanato A. Passaseo 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(1):79-87
Reflectance measurements at variable angle of incidence are performed on GaAs photonic crystal waveguides with unconventional
square lattices. The technique yields the dispersion of photonic bands for the investigated lattices, as first shown by Astratov
et al. [Phys. Rev. B 60, R16225 (1999)]. A sample with a square lattice of air rings and small air fraction yields narrow resonant structures and
a dispersion of photonic modes close to that of free photons. Another sample with a square lattice of dielectric squares and
large air fraction leads to broader structures and to a dispersion of photonic modes which differs strongly for the two polarizations
of light: this sample has a pseudo-gap around 1 micron wavelength. The experimental results are in good agreement with theoretical
calculations of the reflectance and of the photonic mode dispersion in the photonic crystal slabs.
Received 16 January 2002 相似文献
12.
It has been shown by Yu. M. Golubev, M. I. Kolobov, and I. V. Sokolov, Zh. éksp. Teor. Fiz. 111, 1579 (1997) [JETP 84, 864 (1997)], that when an optical cavity is excited by external radiation from a sub-Poisson laser the cavity mode may be
in either a sub-Poisson or a Poisson stationary state. This is not important for a resonant medium which is excited into the
upper laser level while interacting with this mode inside the cavity. The degree of regularity of the excitation will be identical
to that of the initial light flux incident on the cavity, and this ultimately ensures the same sub-Poisson lasing as for strictly
regular pumping of the resonant medium.
Zh. éksp. Teor. Fiz. 113, 1223–1234 (April 1998) 相似文献
13.
D.J. Ewins 《Journal of sound and vibration》1975,43(4):595-605
A simple method is proposed for estimating the resonant peak response levels of damped structures, by using an analysis of undamped vibration. The method is based on a simple identity which is exact for a single degree of freedom system and approximate for more general systems. However, since the level of damping in practical structures can seldom be described with any precision, it is argued that a simple approximate method for predicting resonant vibration levels is the most appropriate. A number of examples and applications are described. 相似文献
14.
Antonio Zecca 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,37(1):151-152
We comment on the recent claim by Karwasz [Eur. Phys. J. D 35, 267 (2005)] that he observed resonant structures in the total cross-section for positron scattering from helium. We frame
our observations in terms of both the general capabilities of the Trento spectrometer, and new checks we have made on the
measurement procedure employed by Karwasz. We conclude that the observed structures are most likely an experimental artefact,
rather than being due to the positron-helium interaction. 相似文献
15.
In this paper the aggregates of the chiral organolithium N-Boc-2-lithiopiperidine [Boc=CO2C(CH3)3], which play an important role in the formation of chiral 2-substituted piperidines found in many alkaloid structures and medicinal compounds, have been investigated within the framework of Density Functional Theory (DFT) calculations. In the complex structures, the lithium atoms are tetra-coordinated, the diaminoalkoxide ligand is tridentate to one lithium atom and forms a chelate with the substrate which is stabilized by the solvent diethyl ether. The same type of bonding was observed for all the different ligand-bound structures; for ligands 6 and 7, which have bulky substituents, selectivity was in agreement with experiment. The results shed light on the microscopic structures of these species and suggest a potential ligand, 11, to yield high enantioselectivity. 相似文献
16.
A. A. Zakharova 《Physics of the Solid State》1998,40(11):1923-1928
The resonant tunneling of electrons through quasistationary levels in the valence band of a quantum well in double-barrier
structures based on III–V materials with type-II heterojunctions is considered in a quantizing magnetic field directed perpendicularly
to the interfaces. The transmission coefficients of the tunnel structure for transitions from states corresponding to different
Landau levels are calculated using the Kane model. It is shown that transitions with a unit change in the Landau level index
n as a result of mixing of the wave functions of states with opposite spin orientations are possible on the interfaces due
to spin-orbit coupling. The probability of such transitions can be comparable to the probability of transitions without a
change in the Landau level index for InAs/AlGaSb/GaSb resonant-tunneling structures.
Fiz. Tverd. Tela (St. Petersburg) 40, 2121–2126 (November 1998) 相似文献
17.
V. V. Kapaev Yu. V. Kopaev S. A. Savinov V. N. Murzin 《Journal of Experimental and Theoretical Physics》2013,116(3):497-515
The characteristics of the high-frequency response of single- and double-well resonant tunneling structures in a dc electric field are investigated on the basis of the numerical solution of a time-dependent Schrödinger equation with open boundary conditions. The frequency dependence of the real part of high frequency conductivity (high-frequency response) in In0.53Ga0.47As/AlAs/InP structures is analyzed in detail for various values of the dc voltage V dc in the negative differential resistance (NDR) region. It is shown that double-well three-barrier structures are promising for the design of terahertz-band oscillators. The presence of two resonant states with close energies in such structures leads to a resonant (in frequency) response whose frequency is determined by the energy difference between these levels and can be controlled by varying the parameters of the structure. It is shown that, in principle, such structures admit narrow-band amplification, tuning of the amplification frequency, and a fine control of the amplification (oscillation) frequency in a wide range of terahertz frequencies by varying a dc electric voltage applied to the structure. Starting from a certain width of the central intermediate barrier in double-well structures, one can observe a collapse of resonances, where the structure behaves like a single-well system. This phenomenon imposes a lower limit on the oscillation frequency in three-barrier resonant tunneling structures. 相似文献
18.
I. V. Altukhov M. S. Kagan K. A. Korolev V. P. Sinis E. G. Chirkova M. A. Odnoblyudov I. N. Yassievich 《Journal of Experimental and Theoretical Physics》1999,88(1):51-57
The stimulated emission spectrum of uniaxially strained p-Ge is presented. The energy spectrum of the states of a shallow acceptor in Ge under uniaxial compression is calculated.
The threshold pressure at which the acceptor state split off from the ground state becomes resonant is found. The pressure
dependence of the width of this resonant level is calculated. The stimulated emission lines are identified. In particular,
it is shown that the principal emission peak corresponds to the transition of holes from the resonant 1s (1s
r) state to the local p
±1 state. The probabilities of optical transitions are calculated. A mechanism of population inversion due to the intense resonant
scattering of hot holes with an energy corresponding to the position of the 1s
r level is proposed.
Zh. éksp. Teor. Fiz. 115, 89–100 (January 1999) 相似文献
19.
N. N. Ledentsov 《Physics of the Solid State》1998,40(5):775-777
New type of structures for optoelectronics, we refer to as excitonic waveguides, are proposed and realized. Oppositely to
conventional waveguides and double-heterostructure lasers, no significant difference in the average refractive index between
the cladding and the active layers is necessary, and these regions can be fabricated from the same matrix material (homojunction
laser). In this approach: (i) the waveguiding effect has a resonant nature and appears on the low-energy side of the strong
exciton absorption peak in agreement with the Kramers-Kronig transformation; (ii) the absorption peak is induced by nanoscale
island-like insertions of narrow-gap material in a wide bandgap matrix (quantum dots), preventing free-carrier screening of
excitons and, simultaneously, allowing lasing resonant to the spectral range of the enhanced refractive index.
Fiz. Tverd. Tela (St. Petersburg) 40, 843–845 (May 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
20.
T. Amthor J. Denskat C. Giese N. N. Bezuglov A. Ekers L. S. Cederbaum M. Weidemüller 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(3):329-335
We investigate a possible mechanism for the autoionization of ultracold Rydberg gases, based on the resonant coupling of Rydberg
pair states to the ionization continuum.
Unlike an atomic collision where the wave functions begin to overlap,
the mechanism considered here involves only the long-range dipole
interaction and is in principle possible in a static system.
It is related to the process of intermolecular Coulombic decay (ICD).
In addition, we include the interaction-induced motion of the atoms and the effect of multi-particle systems in this work.
We find that the probability for this ionization mechanism can be increased in many-particle systems featuring attractive
or repulsive van der Waals interactions. However, the rates for ionization through resonant dipole coupling are very low.
It is thus unlikely that this process contributes to the autoionization of Rydberg gases in the form presented here, but it
may still act as a trigger for secondary ionization
processes.
As our picture involves only binary interactions, it remains to be investigated if collective effects of an
ensemble of atoms can significantly influence the ionization probability.
Nevertheless our calculations may serve as a starting point for the investigation of more complex systems, such as the coupling
of many pair states proposed in [P.J. Tanner et al., Phys. Rev. Lett. 100, 043002 (2008)]. 相似文献