The effect of radiation losses in localized fluorescence upon laser pumping of fluorescent random media

Saturated Emission States in Fluorescent Nanostructured Media: The Role of Competition between the Stimulated Emission and Radiation Losses in the Local Emitters of Fluorescence

“…As follows from Figure 10 a–c, the estimated values of are between 20 µm and 30 µm ( 25 µm; 28 µm; 25 µm). On the other hand, the previously obtained estimated values of for 532 nm-pumped dense random media [ 48 ] are between 70 nm and 100 nm; the corresponding values of are between 0.002 and 0.004. Accordingly, the extreme value of in the case of green laser pumping is expected to be between 17 µm and 50 µm.…”

“…This decrease can be taken into account by introducing the factor of radiation exchange : . In particular, the phenomenological model of radiation exchange in an ensemble of speckle-associated emitters uniformly distributed in a pumped multiple scattering medium [ 48 ] leads to the following expression for : where is the characteristic size of the bulk laser speckles in the medium, and is the dimensionless structural parameter of the speckle field related to the ratio of the average distance between the neighboring speckles to . Note that, in the framework of the considered model, the following relationship is considered: .…”

“…In particular, the phenomenological model of radiation exchange in an ensemble of speckle-associated emitters uniformly distributed in a pumped multiple scattering medium [48] leads to the following expression for rad K :…”

“…This decrease can be taken into account by introducing the factor of radiation exchange K rad << 1: σ rad ≈ K rad /n 0 d em . In particular, the phenomenological model of radiation exchange in an ensemble of speckle-associated emitters uniformly distributed in a pumped multiple scattering medium [48] leads to the following expression for K rad :…”