Based on the analysis of experimental data on the effect of the pulsed laser pump intensity on the spectral properties and the size of the fluorescent response zone in randomly inhomogeneous fluorescent layers, we found that the amplification of spontaneous and stimulated emission significantly affects the statistical properties of the propagation lengths of the fluorescent field partial components in the layers. The experiments are performed with layers of SiO₂ and TiO₂ nanoparticles saturated with rhodamine 6G, pumped by 532-nm laser radiation in the intensity range corresponding to the transient regime from excitation of spontaneous fluorescence to random lasing in the layer. The experimental data are compared with the results of statistical modelling of fluorescence transfer. It is shown that, even at a pump intensity below the random lasing threshold, the spontaneous emission amplification in a layer leads to a significant increase in the contributions to the fluorescence response from partial components with propagation lengths much larger than the layer thickness. This can be interpreted as a manifestation of the quasi-waveguide effect, in which the probability of propagation of diffuse fluorescence components along the layer over distances many times greater than its thickness and the size of the pumped region increases significantly with a decrease in the characteristic radiation amplification length in the layer.

通过对脉冲激光泵浦强度对随机不均匀荧光层中的光谱特性和荧光响应区大小影响的实验数据分析，我们发现自发发射和受激发射的放大显着影响了光谱特性的统计特性。层中荧光场部分分量的传播长度。实验用 SiO ₂和 TiO _2层进行用罗丹明 6G 饱和的纳米粒子，由 532 nm 激光辐射泵浦，其强度范围对应于从激发自发荧光到层中随机激光的瞬态状态。将实验数据与荧光转移的统计建模结果进行比较。结果表明，即使泵浦强度低于随机激光阈值，层中的自发发射放大也会导致传播长度远大于层厚度的部分分量对荧光响应的贡献显着增加。这可以解释为准波导效应的一种表现，