Meanwhile , we take further researchs into the property of spontaneous emission of a two - level atom embedded in photonic crystals , one - dimensional comblike photonic crystals for example 然后以一维梳状光子晶体中原子的自发辐射为例进行深入研究。
In this paper , starting from the fundament theories for the description of the spontaneous emission , the property of spontaneous emission of a two - level atom embedded in photonic crystals was first investigated 本文先从一般理论出发，对光子晶体中两能级原子的自发辐射特性进行了研究。
Therefore it is considered that the spontaneous emission of atom is caused by the fluctuation of dipole moment , not by the dipole moment oscillation of the atomic system 原子偶极矩的期待值总是零，但偶极矩的起伏恒等于一个不为零的常数，因此，原子的自发辐射是由偶极矩的涨落引起的，并非原子偶极矩振荡造成的结果。
However , in the pulse application fields , the output pulse energy from single mode fiber lasers or amplifiers is limited by amplified spontaneous emission ( ase ) , nonlinear effect and facet damage 在脉冲激光应用领域中,这类小芯径光纤放大器和激光器的输出脉冲能量受限于自发辐射放大、非线性效应以及光纤的端面损伤。
Furthermore , when the hybrid spheres are dispersed in the polymers with different refractive index , the spontaneous emission rate of the eu3 + ions is modified due to the dielectric confinement effect 将稀土配合物sio _ 2微球分散在介电常数不同的聚合物介质中，折射率边界引起的介电限域效应改变了稀土离子的自发辐射速率。
Many novel physical phenomena such as coherent population trapping , lasing without inversion , electromagnetically induced transparency as well as spontaneous emission cancellation and enhancement based on quantum interference have been discovered 基于量子干涉效应，产生了许多新的物理现象和效应，如相干布居捕获、无反转激光、电磁感应透明和自发辐射相消等。
There are many optical depletion mechanisms , such as diffraction depletion , the transimission of a reflector , scattering of the medium in the cavity , non - life absorption and so on , so the quality factor ( q factor ) is low . in 利用这种微谐振腔制作的激光器,其自发辐射频率落在光子晶体的禁带范围内,有效降低了激光振荡的阈值,从而使激光器具有低阈值高效的特点。
The amplified spontaneous emission ( ase ) is studied . both the forward and backward ase is simulated and their characters are analyzed in detail . then the dual stage cascade structure is presented as a solution to reduce the ase noise 2 .研究了edfa中放大的自发辐射噪声光( ase ) ,详细分析了前后向ase噪声光的性质,在此基础上,提出了双段级联结构抑制ase噪声光,并对这种方法进行了理论和实验研究。
The resonant dressed transition and the spontaneous decay of the other transition constitute a two - step pathway of population transfer from one dressed state to the other . as the consequence , the population is trapped in one dressed state 此时共振的相干跃迁与另一通道的自发辐射组成一个二步通道，将原子布居从一个修饰态经过辅助能级转移到另一个修饰态，结果产生原子布居在一个修饰态上的捕获。
4 . the lpfgs are used in single wavelength er - doped fiber amplifiers ( edfas ) as a spontaneous emission noise ( ase ) filter , and the gain of the edfa is increased by 7db and the noise figure ( nf ) is decreased by 0 . 5db , for the first time 4 、成功研制了掺铒光纤放大器,首次将高频co2激光脉冲写入的长周期光纤光栅应用到掺铒光纤放大器中作为自发辐射噪声滤波器,使edfa的增益提高了7db 、噪声系数降低了0 . 5db 。
