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1.
We treat the semiclassical equations and the Fokker-Planck equation of a two-photon laser with one or two injected signals and treat both the degenerate and nondegenerate case. The resulting behaviour in the two-photon laser is discussed by means of potential functions which allows one to determine the stable, unstable, and metastable states. 相似文献
2.
M. Brambilla F. Castelli L. A. Lugiato E. M. Pessina F. Prati G. Strini P. Galatola 《Applied physics. B, Lasers and optics》1992,55(3):190-201
We review the main results obtained recently by our group in the field of quantum noise reduction in nonlinear optical systems. We illustrate the possibility of obtaining significant effects in degenerate parametric oscillators, intracavity second-harmonic generation, nondegenerate four-wave mixing, and one- and two-photon optical bistability. 相似文献
3.
Min Shui Zhongguo Li Xiao Jin Junyi Yang Zhongquan Nie Guang Shi Xingzhi Wu Kun Yang Xueru Zhang Yuxiao Wang Yinglin Song 《Optics Communications》2012,285(7):1940-1944
We expand the degenerate PO pump-probe technique to nondegenerate field and use it to investigate optical nonlinear dynamics in ZnS single crystal. Excited by 532-nm laser pulses with 21-ps duration, the temporal response of nondegenerate nonlinear absorption and nondegenerate nonlinear refraction are probed by laser pulses from optical parameter generation (OPG) at 600 and 680 nm with pulse width of 10 ps. Based on the theory of free-carrier optical nonlinearity, we study the pure free-carrier refraction in ZnS. By numerically fitting based on the nondegenerate pump-probe theory, the nondegenerate two-photon absorption coefficient, the free-carrier lifetime, the free-carrier absorptive cross section and refractive coefficient at both probe wavelengths are determined respectively. The dispersion of the free-carrier refractive coefficients is discussed. 相似文献
4.
We present an analytic solution to the "degenerate quantum control problem," which enables the transfer of any desired fraction of population between arbitrary initial and final pure wave packets, made up of nearly degenerate energy eigenstates. It consists of two two-photon adiabatic passage steps, in which the population of the initial wave packet is first transferred, via a number of nondegenerate intermediate states, to a single eigenstate and then returned to a different target superposition state. We demonstrate the approach by executing a stepwise isomerization of three Jahn-Teller states of the Al3O molecule, where a proper optical coupling can easily be established. 相似文献
5.
Coherent Phase Control of Ultrafast Polarization Beats in Reverse V-Type Three-Level System
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We investigate the third-order nonlinear absorption and dispersion of femto- and atto-second polarization beats between the one-photon degenerate four-wave mixing process and the two-photon nondegenerate four-wave mixing process in the pure homogeneously-broadened reverse V-three-level using twin noisy fields. The third-order nonlinear response can be controlled and modified by the colour-locked correlation of twin noisy fields. Most importantly, the coherent phase control in optical heterodyne detection for studying the phase dispersion of the third-order susceptibility is demonstrated. The radiation-matter detuning oscillation is also considered in the freauencv domain. 相似文献
6.
研究了级联三能级系统中孪生色锁随机光场的相位共轭阿秒和频极化拍频(ASPB)不对称新效应。从理论上分析了自关联单光子简并四波混频(DFWM)和双光子非简并四波混频(NDFWM)信号辐射场与物质间不对等效应、混合型太赫兹失谐振荡特性,及双光子非简并共振四波混频信号的延时不对称性;同时也分析了由干涉计两臂不平衡色散效应引起的阿秒和频极化拍频信号的延时不对称性,即阿秒和频极化拍频信号的最大值相对于零延时有一个小偏移,结果表明该不对称性并这不影响阿秒和频极化拍频零差探测两偶极禁戒跃迁能级分裂的总体精度。阿秒和频极化拍频作为一种消除多普勒增宽的超快调制过程,从理论上说它可以扩展到任何两偶极禁戒跃迁能级系统。 相似文献
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A striking feature of quantum error correcting codes is that they can sometimes be used to correct more errors than they can uniquely identify. Such degenerate codes have long been known, but have remained poorly understood. We provide a heuristic for designing degenerate quantum codes for high noise rates, which is applied to generate codes that can be used to communicate over almost any Pauli channel at rates that are impossible for a nondegenerate code. The gap between nondegenerate and degenerate code performance is quite large, in contrast to the tiny magnitude of the only previous demonstration of this effect. We also identify a channel for which none of our codes outperform the best nondegenerate code and show that it is nevertheless quite unlike any channel for which nondegenerate codes are known to be optimal. 相似文献
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The categories of optical bistability within a nondegenerate two-beam, two-photon resonant system are presented and discussed. 相似文献
12.
We start from the microscopic Hamiltonian formulated by means of creation and annihilation operators for the field modes, and creation and annihilation operators for the electrons. The virtual transitions via the intermediate atomic level are eliminated by second order perturbation theory so that an effective Hamiltonian results which describes two-photon creation or annihilation. In the next step Heisenberg equations of motion are derived for the field amplitudes, the atomic dipole moments, and the inversion. The effect of heatbaths is taken into account by means of damping terms and fluctuating forces. In the present paper these equations are averaged over the fluctuating forces and the resulting semiclassical equations are solved for the stationary state. We treat the degenerate and nondegenerate case including detuning and atomic levels with homogeneous and inhomogeneous broadening. The field modes may be either running or standing waves. A detailed discussion of the laser condition is given. 相似文献
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A. M. Ermolaev G. I. Rashba M. A. Solyanik 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,73(3):383-388
Thermodynamic functions have been calculated in the effective mass
approximation for degenerate and nondegenerate electron gases on the
semiconductor cylindrical nanotube surface in a longitudinal magnetic field.
The Laplace transform linking the density of states and the statistical sum
has been used. The thermodynamic quantities of degenerate electron gas
undergo the de Haas-van Alphen oscillations with the electron Fermi energy
change and the Aharonov-Bohm oscillations with the magnetic flux change
within the semiconductor tube cross section. The quantities related to
nondegenerate gas oscillate only with the change of magnetic flux. A peak
has been found in the nondegenerate gas heat capacity-temperature diagram. A
limiting process to 2D electron gas on plane has been carried out. 相似文献
15.
Laser actions and photon statistics far a nondegenerate two-photon laser in an effective three-level stomic system with arbitrary detunlng are Investigated both semiclassically and quantum meehmleally, Due to the two-photon effect, the radiation field easily displays a sub-Foissonian statlstieal distribution. The laser actions for a two-photon and a sihgle-photon loss mechanisms are compared. It is found that the detailed balance in the single-photon loss mechanism can still be preserved in the case that a first-order phase transtion takes place. 相似文献
16.
Xun-Li Feng Zhao-Yang Chen Zhi-Zhan Xu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,7(1):117-121
The nondegenerate two-photon interaction of a two-level atom with a broadband multimode squeezed vacuum is investigated. We
find that in the two-photon process the squeezed vacuum has a driving effect on the atom which can lead to an ac Stark effect
when the average photon number of the squeezed vacuum is larger than a critical value.
Received: 2 February 1999 / Received in final form: 20 April 1999 相似文献
17.
P. V. Mikheev 《Radiophysics and Quantum Electronics》2006,49(7):564-571
We obtain an analytical expression for the probability density of the Gaussian vector with a degenerate covariance matrix.
The expression generalizes a similar expression for the nondegenerate case. A definition of the Gaussian vector on the basis
of a probability density, which is common for the degenerate and nondegenerate cases, is given. Examples of using the obtained
probability density for the synthesis of optimal signal-processing algorithms are presented.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 7, pp. 626–634, July 2006. 相似文献
18.
附加克尔介质简并双光子J-C模型的动力学特性 总被引:8,自引:0,他引:8
本文利用密度算符间的距离研究了附加克尔介质简并双光子Jaynes-Cummings模型(JCM)的动力学特性.在与标准简并双光子Jaynes-Cummiungs模型以及附加克尔介质单光子Jaynes-Cummings模型相比较的基础上,详细讨论了克尔介质非线性相互作用对该模型动力学行为的影响. 相似文献
19.
《Physics letters. A》2019,383(19):2277-2284
Small and large amplitude linear and nonlinear ion acoustic and Langmuir waves are investigated for plasma with the generalized equation of state (EoS). This EoS covers a wide range of energy-density conditions from dilute classical regime up to the relativistically degenerate matter. Investigation shows that the linear dispersion and localized excitations of ion acoustic waves are significantly affected by the plasma parameters. It is also found that the criterion for ordinary soliton existence is significantly different for fully degenerate and nondegenerate plasma regimes with given electron temperature. In the nondegenerate regime, bright solitons form only for Mach numbers above a critical value which is only a function of the fluid temperature. 相似文献