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1.
Output power spectrum of a single-mode laser driven by coloured pump and quantum noises with coloured correlation 下载免费PDF全文
By using the linear approximation method, the output power spectrum is calculated for a single-mode laser driven by coloured pump and quantum noises with coloured correlation. We have observed that the configuration of the output power spectrum is complicated: that is, it can be of single peak, two peaks or three peaks. The configurations of the power spectrum can be transformed from one into another by changing the cross-correlation time, the cross-correlation coefficient between the two noises, and pump noise intensity. 相似文献
2.
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
3.
Stochastic resonance in a gain--noise model of a single-mode laser driven by pump noise and quantum noise with cross-correlation between real and imaginary parts under direct signal modulation 下载免费PDF全文
Stochastic resonance (SR) is studied in a gain--noise model of a
single-mode laser driven by a coloured pump noise and a quantum noise
with cross-correlation between real and imaginary parts under a
direct signal modulation. By using a linear approximation method, we
find that the SR appears during the variation of signal-to-noise
ratio (SNR) separately with the pump noise self-correlation time
\tau , the noise correlation coefficient between the real part and
the imaginary part of the quantum noise \lambdaq , the
attenuation coefficient \gamma and the deterministic steady-state
intensity I_0 . In addition, it is found that the SR can be
characterized not only by the dependence of SNR on the noise
variables of \tau and \lambdaq, but also by the
dependence of SNR on the laser system variables of \gamma and I0. Thus our investigation extends the characteristic quantity of SR
proposed before. 相似文献
4.
The statistical fluctuation of a single-mode laser system driven by coloured pump noise with signal modulation and the quantum noise with cross-correlation between its real and imaginary parts 下载免费PDF全文
Using the linear approximation method, this paper studies the statistical property
of a single-mode laser driven by both coloured pump noise with signal modulation and
the quantum noise with cross-correlation between its real and imaginary parts, and
calculates the steady-state mean normalized intensity fluctuation and intensity
correlation time. It analyses the influences of the modulation signal, the net gain
coefficient, the noise and its correlation form on the statistical fluctuation of
the laser system respectively. It is found that the coloured pump noise modulated by
the signal has a great suppressing action on the statistical fluctuation of the
laser system; the pump noise self-correlation time and the specific frequency of
modulation signal have the result that the statistical fluctuation tends to zero.
Furthermore, the `colour' correlation of pump noise has much influences on the
statistical fluctuation of the laser system. Increasing the intensity of pump noise
will augment the statistical fluctuation of the laser system, but the intensity of
quantum noise and the coefficient of cross-correlation between its real and
imaginary parts have less influence on the statistical fluctuation of the laser
system. Therefore, from the conclusions of this paper the statistical property can
be known and a theoretical basis for steady operation and output of the laser system
can be provided. 相似文献
5.
在色噪声间的关联程度受时间周期调制的激光系统中,研究噪声受信号调制情况下的随机共振.用线性化近似的方法计算了光强关联函数及信噪比.具体讨论信噪比随噪声强度、噪声自关联时间、信号频率以及时间周期调制频率的变化关系.发现一种新的随机共振:信噪比随时间周期调制频率的变化出现周期振荡型随机共振;发现广义随机共振:信噪比随抽运噪声自关联时间的变化、随信号频率的变化出现随机共振;同时也存在典型的信噪比随噪声强度的变化而出现的随机共振.而信噪比随量子噪声自关联时间的变化表现为抑制.
关键词:
信号调制
时间周期调制
噪声间关联程度
周期振荡型随机共振 相似文献
6.
7.
采用交叉色关联的加性色噪声和乘性色噪声驱动的单模激光立方模型,通过诺维科夫理论和福克斯近似以及斯特拉托诺维奇近似,得到反映激光统计性质的强度关联函数C的表达式;研究关联时间τ、净增益系数a0和交叉关联强度λ对强度关联函数C的影响.数值模拟发现,在阈值以上(a0>0)时,关联函数C随关联时间τ的增大而增大;在阈值以下(a0<0)时,关联函数C随关联时间τ的增大而减小.无论在阈值以上还是阈值以下,关联函数C均随交叉关联强度λ的增大而减小.在C-a0曲线上存在单峰.
关键词:
单模激光
交叉关联
强度涨落
强度关联函数 相似文献
8.
Considering a single-mode laser system with cross-correlated additive colored noise and multiplicative colored noise, we study the effects of correlation among noises on the normalized intensity correlation function C(s).C(s) is derived by means of the projection operator method. 相似文献
9.
CHEN Li-Mei CAO Li WU Da-Jin GE Guo-Qin 《理论物理通讯》2005,44(10)
The effect on intensity correlation time T by input signal is studied for gain-noise model of a single-mode laser driven by colored pump noise and colored quantum noise with colored cross-correlation with a bias signal modulation in this paper. By using the linear approximation method, we detect that there exists maximum (i.e., resonance) in the curve of the intensity correlation time T upon bias-current i0 when the noise correlation coefficient λ is positive; and there exists minimum (i.e., suppression) in the T-i0 curve when λ is negative. And when λ is zero, T increases monotonously with increasing i0. Furthermore, the curve of T upon the signal frequency Ω is also studied. Our study shows that no matter what the value ofλ is, there exists minimum (i.e., suppression) in the T-Ω curve. 相似文献
10.
CHEN Li-Mei CAO Li WU Da-Jin GE Guo-Qin 《理论物理通讯》2005,44(4):638-642
The effect on intensity correlation time T by input signal is studied for gain-noise model of a single-mode laser driven by colored pump noise and colored quantum noise with colored cross-correlation with a bias signal modulation in this paper. By using the linear approximation method, we detect that there exists maximum (i.e., resonance) in the curve of the intensity correlation time T upon bias current io when the noise correlation coefficient λ is positive; and there exists minimum (i.e., suppression) in the T-io curve when λ is negative. And whenλ is zero, T increases monotonously with increasing io. Furthermore, the curve of T upon the signal frequency Ω is also studied. Our study shows that no matter what the value of λ is, there exists minimum (i.e., suppression) in the T-Ω curve. 相似文献
11.
Stochastic resonance in a single-mode laser driven by frequency modulated signal and coloured noises 下载免费PDF全文
By adding frequency modulated signals to the intensity equation of
gain--noise model of the single-mode laser driven by two coloured
noises which are correlated, this paper uses the linear
approximation method to calculate the power spectrum and
signal-to-noise ratio (SNR) of the laser intensity. The results show
that the SNR appears typical stochastic resonance with the variation
of intensity of the pump noise and quantum noise. As the amplitude
of a modulated signal has effects on the SNR, it shows suppression,
monotone increasing, stochastic resonance, and multiple stochastic
resonance with the variation of the frequency of a carrier signal
and modulated signal. 相似文献
12.
Statistical properties of a single-mode laser driven by additive and multiplicative coloured noises with a coloured cross-correlation for different correlation times 总被引:2,自引:0,他引:2 下载免费PDF全文
We study a system for a single-mode laser driven by additive and multiplicative coloured noises with a coloured cross-correlation. The analytical expression of the stationary intensity distribution (SID) for the laser is derived in the case of three different correlation times. The influences of each stochastic parameter on the SID are discussed, the effects of the noise "colour" and the cross-correlation of noises on the mean intensity , the variance, λ_2(0), and the skewness,λ_3(0) of the single-mode laser are investigated. We find that there are colourful phase transitions for the SID above a threshold, and re-entrant transitions induced by the "colour" of the additive noises. Further research of the curves of -τ_i, λ_2(0)-τ_i, and λ_3(0)-τ_i (i=1,2,3) (where τ_i is the correlation time) shows that the output intensity not only increases with the additive noise correlation time τ_2 and the cross-correlation time τ_3, but also the quality of the output of laser beams is optimized. 相似文献
13.
Time evolution of the intensity correlation function in a single-mode laser driven by both the coloured pump noise with signal modulation and the quantum noise with cross-correlation between the real and imaginary parts 下载免费PDF全文
Using the linear approximation, we have studied the time evolution of intensity correlation function C(t) in a single-mode laser driven by both the colored pump noise with signal modulation and the quantum noise with cross-correlation between its real and imaginary parts. In the case of the pump noise self-correlation time, we find that the time evolution of C(t) varies with modulation signal frequency Ω, amplitude B, and net gain ɑ0. (i) As the Ω increases, the time evolution of C(t) experiences a process changing from the monotonous descension to the descension with a flat appearing initially, and finally to the a form of damping oscillation; (ii) As the B increases, it experiences from monotonous descension to the appearance of a maximum; (iii) As the net gain ɑ0 increases, it experiences a process repeatedly changing from the monotonous descension to monotonous ascension, and to the appearance of a maximum, finally to monotonous descension again. However, in the case of, the time evolution of C(t) only exhibits a form of damping oscillation . 相似文献
14.
15.
HAN Li-Bo CAO Li WU Da-Jin WANG Jun 《理论物理通讯》2004,42(7)
By using the linear approximation method, the intensity correlation function and the intensity correlation time are calculated in a gain-noise model of a single-mode laser driven by colored cross-correlated pump noise and quantum noise, each of which is colored. We detect that, when the cross-correlation between both noises is negative, the behavior of the intensity correlation function C(t) versus time t, in addition to decreasing monotonously, also exhibits several other cases, such as one maximum, one minimum, and two extrema (one maximum and one minimum), i.e., some parameters of the noises can greatly change the dependence of the intensity correlation function upon time. T3. 相似文献
16.
17.
Intensity Correlation Function of a Single-Mode Laser Driven
by Two Colored
Noises with Colored Cross-Correlation 总被引:1,自引:0,他引:1
HANLi-Bo CAOLi WUDa-Jin WANGJun 《理论物理通讯》2004,42(1):59-63
By using the linear approximation method, the intensity correlation function and the intensity correlation time are calculated in a gain-noise model of a single-mode laser driven by colored cross-correlated pump noise and quantum noise, each of which is colored. We detect that, when the cross-correlation between both noises is negative, the behavior of the intensity correlation function C(t) versus time t, in addition to decreasing monotonously, also exhibits several other cases, such as one maximum, one minimum, and two extrema (one maximum and one minimum), i.e., some parameters of the noises can greatly change the dependence of the intensity correlation function upon time. Moreover, we find that there is a minimum Tmin in the curve of the intensity correlation time versus the pump noise intensity, and the depth and position of Train strongly depend on the quantum noise self-correlation time T2 and cross-correlation time T3. 相似文献
18.
19.
By using the linear approximation method, the intensity
correlation function is calculated for a single-mode laser modulated
by a bias signal and driven by colored pump and quantum noises
with colored cross-correlation. We found that, when the correlation
time between the two noises is very short, the behavior of the
intensity correlation function versus the time, in addition to
decreasing monotonously, also exhibits several cases, such as
one maximum, one minimum, and two extrema. When the correlation
time between the two noises is very long, the behavior of the
intensity correlation function exhibits oscillation and the envelope
is similar to the case of short cross-correlation time. 相似文献