Multiple scattering and nonlinear thermal emission of Yb3+,Er3+:Y2O3 nanopowders

摘要: Radiation transport and multiple scattering calculations are presented compared with experimental observations to characterize light attenuation in high emissivity nanopowders irradiated low power laser at room temperature, explain the associated white emission onset of melting. Using radiation tuned an absorption resonance Yb3+ dopants Y2O3 nanopowder, we observed intense blackbody above a well-defined intensity threshold. Local melting compact threshold leads formation single crystal microtubes. Evidence is provided show that two-flux theory diffusion both significantly underestimate due dependent, for thermal runaway process responsible this behavior very sensitive porosity random medium.