LASING ACTION FROM RANDOM-MEDIA WITH GAIN

Photon processes in scattering media with optical gain has recently at tracted much interest because of the possibility of getting strong, mo nochromatic, laser-like light emission at low cost. We present here ex perimental results showing the properties of optically pumped dyed tit anate solutions. In particular we introduce a mapping technique showin g the existence of several physical mechanisms depending on the titana te particles density and the dye concentration. We also suggest the po ssibility of locking the light emission at a specific wavelength using the scatterers properties only. (C) 1997 Elsevier Science B.V.