共查询到19条相似文献,搜索用时 109 毫秒
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采用线性化近似,计算了由具有色关联的受偏置信号调制的色泵噪声和色量子噪声驱动 的单模激光增益模型的光强相对涨落,发现相对涨落随噪声强度的变化曲线中存在极小值,分析了偏置信号的强度、周期信号频率、噪声间的互关联强度和互关联时间对曲线的影响; 对单模激光增益模型在偏置信号调制和直接信号调制两种方式下的输出光强相对涨落进行了比较,发现光强涨落与偏置信号的强度密切相关.
关键词:
偏置信号调制
光强相对涨落
线性化近似 相似文献
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基于分数阶朗之万方程和随机行走理论, 建立了一种用于研究非马尔可夫系统中随机变量随时间演化的数值模拟算法, 称之为分数阶随机行走模拟法. 进一步运用此算法分别数值研究了无阻尼有涨落、 有阻尼无涨落和阻尼与涨落兼备三种情况下, 受欠扩散分数阶朗之万方程约束的随机变量随时间的演化行为. 结果显示阻尼和涨落存在竞争关系: 高斯型涨落的影响会随着时间的增长被"抹平", 从而凸显阻尼使系统趋于平衡的作用; 而长尾型涨落则由于包含"小概率大贡献"事件, 使得长时间演化之后系统变量仍以一定概率出现突然变化.
关键词:
非马尔可夫
欠扩散
阻尼与涨落
分数阶朗之万方程 相似文献
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对不同参数的掺钕晶体双频微片激光器(DFML)进行频差温度特性研究.探索了在不同腔长、不同种类掺钕介质的DFML中,晶体温控温度对双频信号频差的影响.结果表明,双频信号频差与谐振腔光学腔长成反比,与晶体温控温度呈正相关;其中0.5mm腔长DFML(Nd∶YVO_4)的双频信号频差随晶体温控温度的变化率为0.34GHz/℃,0.8mm腔长DFML(Nd∶YVO4)的双频信号频差随晶体温控温度的变化率为0.12GHz/℃,1mm腔长DFML(Nd∶YVO_4)的双频信号频差随晶体温控温度的变化率为0.044GHz/℃;即腔长越短,晶体温控温度对频差的影响越大.不同材料Nd∶YVO_4和Nd∶GdVO_4晶体1mm腔长的DFML双频信号频差随晶体温度的变化率相近,仿真与实验结果符合较好. 相似文献
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测量了 Y_1Ba_2Cu_3O_(7-δ)氧化物超导材料的电阻随温度变化曲线,观察到 T≥T_c 时电阻比线性外推下来的 R_n(T)小.我们把它解释为热力学涨落效应.从实验结果计算出了涨落电导率随温度的变化,并作了理论计算,两者作了比较.在一些情况下求出了相干长度. 相似文献
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基于产生光电探测器噪声信号{V_i}的随机过程,分析了随机测量中稳定不变与随机涨落两部分的不同性质,建立了噪声信号随机性数学模型,分析得出在随机性统计研究中对统计分布函数的非线性约束关系.实验研究了同一随机过程中不同性质特征量随机涨落的统计计数规律,如随机噪声信号幅度值、极值幅度、极值间隔,相邻幅度差、乘积复合特征量、商复合特征量等随机特征量涨落统计分布规律均满足对数正态分布.从理论和实验上得出对数正态分布在描述随机过程中随机涨落部分性质的重要作用. 相似文献
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讨论了一个双模环型激光增益噪声模型,其中考虑了完全饱和效应且乘法噪声由增益系数涨落引起。在共振及两模具有相同泵参数时,获得了光强联合定态分布的精确解析表达式。通过与现有的双模激光摸型(其中乘法噪声由损失系数涨落引起)的比较,发现乘法噪声系数的非线性效应减弱了乘法噪声给激光光强统计性质带来的反常特性,并且这种减弱随着乘法噪声增强或损失系数减小而愈加明显。 相似文献
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Phase dispersion of Raman and Rayleigh-enhanced four-wave mixings in femtosecond polarization beats 下载免费PDF全文
Based on color-locking noisy field correlation in three Markovian
stochastic models, phase dispersions of the Raman- and
Rayleigh-enhanced four-wave mixing (FWM) have been investigated. The
phase dispersions are modified by both linewidth and time delay for
negative time delay, but only by linewidth for positive time delay.
Moreover, the results under narrowband condition are close to the
nonmodified nonlinear dispersion and absorption of the material.
Homodyne and heterodyne detections of the Raman, the Rayleigh and
the mixing femtosecond difference-frequency polarization beats have
also been investigated, separately. 相似文献
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Coexisting Raman- and Rayleigh-Enhanced Four-Wave Mixing in Femtosecond Polarization Beats 下载免费PDF全文
Based on the polarization interference of Raman- and Rayleigh-enhanced four-wave mixing processes, heterodyne detection of the Raman, Rayleigh and coexisting Raman and Rayleigh femtosecond difference-frequency polarization beats is investigated in the cw and the three Markovian stochastic models, respectively. These two processes exhibit asymmetric and symmetric spectra, respectively, and the thermal effect in them can be suppressed by field-correlation method. Such studies of coexisting Raman- and Rayleigh-enhanced four-wave mixing processes can have important applications in coherence quantum control, and quantum information processing. 相似文献
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Göran Lindblad 《Journal of statistical physics》1993,72(3-4):539-554
Recall that the fluctuation-dissipation theorem connects the response function of a passive linear system and the spectral density of the stationary stochastic process which describes the thermal fluctuations in the system. It is shown that the classical limit (=0) of the fluctuation-dissipation theorem implies a correspondence between systems which are reversible in the sense that the energy used to drive them away from equilibrium is completely recoverable as work and processes which are deterministic in the sense of Wiener's prediction theory, while irreversible systems correspond to nondeterministic processes. This correspondence is expressed by a simple transformation between the operator kernel which determines the optimal choice of the time-dependent force and the linear predictor for the stochastic process. For quantum systems this correspondence does not hold; the fluctuations are always of the deterministic type for any finite temperature, but the system is not necessarily reversible. For irreversible systems a formula is derived for the instantaneous entropy production which is a generalization of the standard one for Markovian dynamics. 相似文献
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V. T. N. Reddy 《Journal of statistical physics》1975,13(1):61-64
Nicolis and Prigogine have shown that the Volterra-Lotka model taken as a Markovian stochastic process does not have a steady state, by considering the Fokker-Planck-type equation for small fluctuations. Here we use the exact master equation to show that the only steady state in the model is the trivial one. 相似文献
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We study the stability of decoherence-free subspaces under stochastic phase fluctuations by analytically and numerically evaluating the fidelity of the corresponding decoherence-free subspace bases with stochastic phase fluctuations under the evolution of environment. The environment is modeled by a bath of oscillators with infinite degrees of freedom and the register-bath coupling is chosen to be a general dissipation-decoherence form. It is found that the decoherence-free subspaces take on good stability in the case of small dissipation and small phase fluctuations. 相似文献
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ZENG Hao-Sheng NIE Jian-Jun KUANG Le-Man 《理论物理通讯》2006,46(3):447-452
We study the stability of decoherence-free subspaces under stochastic phase fluctuations by analytically and numerically evaluating the fidelity of the corresponding decoherence-free subspace bases with stochastic phase fluctuations under the evolution of environment. The environment is modeled by a bath of oscillators with infinite degrees of freedom and the register-bath coupling is chosen to be a general dissipation-decoherence form. It is found that the decoherence-free subspaces take on good stability in the case of small dissipation and small phase fluctuations. 相似文献
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The dynamics of stochastic dust charge fluctuations is investigated. An inhomogeneous Burgers equation with a linear forcing term is derived in which the Burgers term is proportional to the diffusivity of dust charge fluctuations. This novel equation is solved analytically. Possibility of turbulence due to stochastic charge fluctuations is highlighted. 相似文献
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�ܺ������ݾ����ųڣ���ģ������� 《核聚变与等离子体物理》2018,38(3):309-314
为了更好地研究反常输运,J-TEXT发展了一套相关电子回旋辐射(CECE)系统来测量电子温度涨落。该系统采用频率去相关的结构,通过八道窄带滤波器进行频率选择,其中两道采用带宽为100MHz的定频滤波器,其余六道采用带宽为100~240MHz的钇铁石榴石(YIG)滤波器,YIG滤波器的中心频率为数字可调,增加了系统的灵活性。通过光路的优化,系统的极向分辨率最高可达2.5cm-1。实验结果表明系统性能良好,通过互相关技术可以消除热噪声的影响得到电子温度涨落,并且观测到靠近等离子体芯部的电子温度涨落要小于靠近边缘的电子温度涨落。 相似文献