NOVEL STRATEGIE​S FOR ENHANCED RANDOM LASING AND BIOCOMPATIBLE RAMAN LASING
ABSTRACT :
Random lasing, which is a consequence of multiple scattering and amplification of optical waves traveling in an active random medium, has been explored in various systems in the past two decades. In this work, we provide novel methods to demonstrate femtosecond laser pumped-plasmonically enhanced near-infrared random lasing along with an interesting fully biocompatible medium for realising Raman random lasing. The lasing features are validated by observation of threshold and linewidth narrowing. The experimental results are supported with Mie scattering computations and FDTD local-field calculations. The work also provides an approach to realize enhanced random lasing in rhodamine based colloidal random lasers based on morphologically tuned TiO2. Random lasers have potential applications in optical spectroscopy and sensing owing to their multimode spectral behaviour tunable over the gain bandwidth of the active/gain medium.