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1.
AMolecularDynamicalTheoryofUltraweakBio-photonEmissioninLivingSystemsanditsProperties(Ⅱ)AMolecularDynamicalTheoryofUltraweakB...  相似文献   

2.
In this paper we present a theoretical analysis on the determination of the scaling parameter in the complex-rotated Hamiltonian, which has served as a basis for successful applications of the rigged Hilbert space theory for resonances. Based on the complex energy eigenvalue, E(θ) = ER(θ) - iГ(θ)/2, as a function of the scaling parameter θ, we find that for potential barrier scattering, the condition dГ(θI)/dθ = 0 uniquely determines the scaling parameter 8. The condition d ER (θR)/ dθ = 0 is merely a consequence of the Virial theorem and θI =θR is not a necessary condition for a resonance state. We also provide a harmonic approximation formMism for resonances in scattering over a potential barrier.  相似文献   

3.
Expressions are obtained for the intensity and the quantum yield of the sensitized luminescence of the chromophore that plays the role of a reaction center in the simplest model trichromophore molecular [lightcollecting] antenna which is so constructed and so oriented in space that the irradiation photons coherently excite its other two chromophorespigments. The quantum electrodynamics formalism which takes into account the radiative dissipative interaction between the pigments and the reaction center of the antenna was used. The comparative analysis of the obtained expressions with the corresponding expressions for the luminescence of a bichromophore molecular system, differing from the trichromophore antenna by the absence of one of the pigments, has shown that the collective dissipative interaction of the pigments with the reaction center of the antenna can be considered as a highly efficient mechanism of [light collection] in molecular antennas.  相似文献   

4.
We consider a realization of the W_(1+∞) algebra and investigate its n-algebra, which is different from the n-algebra of Zhang et al. [2016 arXiv:1606.07570 v2] It is found that the generators W_m~s with any fixed superindex s ≥ 1 yield the null sub-2 s-algebra. The nontrivial sub-4-algebra and Virasoro-Witt 3-algebra are presented. Moreover,we extend the generators to the multi-variables case. These generators also yield the W_(1+∞) algebra and null n-algebras.  相似文献   

5.
6.
Quantum teleportation of one- and two-photon superposition states based on EPR entanglement of continuous-wave two-mode squeezed state is discussed. The fidelities of teleportation axe deduced for two different input quantum states. The dependence of the fidelity on the parameters of EPR entanglement and the gain of the classical channels are shown numerically. Comparing with the teleportation of Fock state and coherent state, it is pointed out that for given EPR entanglement and classical gain, the higher the nonclassicality of the input state, the lower the accessible fidelity of teleportation.  相似文献   

7.
Based on the concept of the binomial state and the negative-binomial state we introduce a new binomial–negative-binomial combinatorial state in quantum optics theory. We show that such a state can be implemented in the laser channel as an output state when the initial state is a pure number state. The master equation related to the laser channel is solved by virtue of the entangled state representation.  相似文献   

8.
We study the algebraic structure of the one-dimensional Dirac oscillator by extending the concept of spin symmetry to a noncommutative case.An SO(4) algebra is found connecting the eigenstates of the Dirac oscillator,in which the two elements of Cartan subalgebra are conserved quantities.Similar results are obtained in the Jaynes-Cummings model.  相似文献   

9.
Given the initial conditions of spatial density distribution, velocity distribution and mass function, the dynamical evolution of globular clusters in the Milky Way is investigated in details by means of Monte Carlo simulations.Four dynamic mechanisms are considered: stellar evaporation, stellar evolution, tidal shocks due to both the disc and bulge, and dynamical friction. It is found that stellar evaporation dominates the evolution of low-mass clusters and all four are important for massive ones. For both the power-law and lognormM initial clusters mass functions, we can find the best-fitting models which can match the present-day observations with their main features of the mass function almost unchanged after evolution of severM Gyr. This implies that it is not possible to determine the initial mass function only based on the observed mass function today. The dispersion of the modelled mass functions mainly depends on the potential wells of host galaxies with the almost constant peaks,which is consistent with current observations.  相似文献   

10.
11.
Recently some modes of supersonic molecular beam injection (SMBI)have been put forward. Among them there are electrostatic “double layer”-shielding, simple collective and optimized numerical models to explain the experiment phenomenon. The penetrated depth A and particle deposition were calculated theoretically. About 1/7 in- cident thermal electron flux was amputated and, A increased seven times. The previous simulation is not enough for the SMBI fueling mechanism research. Hence, further investigations, both in experiment and in theory should be developed. The phenomena of line emission due to supersonic molecular beam (SMB) are of particular importance.  相似文献   

12.
By using of the invariant theory, we have studied the phase of exciton emission in a semiconductor microcavity, the dynamical and geometric phases are presented respectively. The Aharonov-Anandan phase is also obtained in the case of cyclical evolution.  相似文献   

13.
Using the standard truncated Painleve analysis,we can obtain a Backlund transformation of the (3 1)-dimensional Nizhnik-Novikov-Veselov (NNV) equation and get some(3 1)-dimensional single-,two- and three-soliton solutions and some new types of multisoliton solutions of the (3 1)-dimensional NNV system from the Backlund transformation and the trivial vacuum solution.  相似文献   

14.
张兰  马会中  姚宁  张兵临 《发光学报》2007,28(4):599-603
利用微波等离子体化学气相沉积方法,以甲烷、氢混合气体为反应气体,具有钛镀层的玻璃作为衬底,制备了具有sp1杂化结构的白碳纳米晶薄膜。利用X射线衍射、俄歇电子能谱,以及扫描电子显微镜对薄膜结构进行了表征。以白碳纳米晶薄膜为阴极,以镀有ITO透明导电薄膜玻璃为阳极,采用二极管结构,测试了白碳纳米晶薄膜的场致电子发射特性。开启电场为2.5 V/μm,在电场为5 V/μm时的电流密度为200μA/cm2。对白碳纳米晶薄膜生长机理,以及其场致电子发射机制进行了讨论。  相似文献   

15.
By means of a special Painlevé-Bäcklund transformation and a multilinear variable separation approach, an exact solution with arbitrary functions of the (2+1)-dimensional Boiti-Leon-Pempinelli system (BLP) is derived. Based on the derived variable separation solution, we obtain some special soliton fission and fusion solutions for the higher dimensional BLP system.  相似文献   

16.
We give a birational realization of affine Weyl group of type A (1) m–1 × A (1) n–1. We apply this representation to construct some discrete integrable systems and discrete Painlevé equations. Our construction has a combinatorial counterpart through the ultra-discretization procedure.  相似文献   

17.
Using the extended homogeneous balance method, we obtained abundant exact solution structures of the (3 1 )-dimensional breaking soliton equation. By means of the leading order term analysis, the nonlinear transformations of the (3t1)-dimensional breaking soliton equation are given first, and then some special types of single solitary wave solutions and the multisoliton solutions are constructed.  相似文献   

18.
We report optical gain measurements in four different copolymers polyp-phenylene-co-[2,5-dioctyloxy-p-phenylene-bis-2(4-nonyl phenyl) vinylene]nonyl-PpPV, polym-phenylene-co-[2,5-dioctyloxy-p-phenylene-bis-2(4-methyl phenyl) vinylene]methyl-PmPV, polyp-phenylene-co-[2,5-dioctyloxy-p-phenylene-bis-2(4-methyl-phenyl) vinylene]methyl-PpPV, polyp-phenylene-co-[2,6-naphthylene-bis-2(4-nonyl phenyl) vinylene]nonyl-PpPV-NV in toluene. The copolymers are related to poly(phenylene vinylene) and have been synthesized via Horner–Emmons polycondensation reaction. The optical gain determined from the amplified spontaneous emission (ASE) intensity is dependent on the excited stripe length. The net optical gain coefficients are found to vary between 0.1 cm–1 in nonyl-PpPV to 2.5 cm–1 in methyl-PmPV under nanosecond pulse excitation. The gain for Rodamine 6G was also measured under the same experimental condition and was used to determine the stimulated emission cross-sections for the four polymers and found to be SE(peak)= 6.7 × 10–20 cm2 for nonyl-PpPV, SE(peak)= 1.7 × 1018 cm2 for methyl-PmPV, SE(peak)= 1.4 × 10–18 cm2 for methyl-PpPV, and SE(peak)= 1.5 × 10–18 cm2 for nonyl-PpPV-NV.  相似文献   

19.
HL-2A tokamak, the first tokamak with divertor in China, has been constructed and put into operation in 2002. The main parameters are R=1.65 m, a=0.4 m, BT=2.8 T, Ip = 0. 48 MA. The divertor of HL-2A is unique, because it is characterized with a large closed divertor chamber. The device has double divertor chamber, but now it is operating with lower single null configuration to study the physics of divertor for the next step design of a divertor. Supersonic molecular beam injection (SMBI) system with LN2 cooling trap was first installed and demonstrated on the HL-2A tokamak in 2004. The first results of SMBI into HL-2A plasma are to demonstrate the function of the HL-2A divertor and to observe the cold pulse propagation during multi-pulse SMBI on HL-2A Tokamak.  相似文献   

20.
We observed optical emission of molecular hydrogen in a recombining hydrogen plasma with an electron temperature of 0.1 eV and an electron density of 3 × 1012cm–3. The optical emission intensities of molecular hydrogen in the recombining plasma were roughly 10%–45% of those in an ionizing plasma with an electron temperature of 4 eV. The ratio was greater for a transition line originated from an excited state with a larger vibrational quantum number. Because of the low electron temperature of 0.1 eV, the production processes of excited states are not considered electron impact excitation in the recombining plasma. Possible recombination processes are discussed which produce excited states of molecular hydrogen in the recombining plasma (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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