FIRST EVIDENCE OF STIMULATED-EMISSION FROM A MONOLITHIC ORGANIC SINGLE-CRYSTAL - ALPHA-OCTITHIOPHENE

The gag between laser dyes and luminescent polymers - on the way to th e polymer laser diode-is bridged by conjugated oligothiophenes, accord ing to the results reported here. Evidence for optically pumped spectr al narrowing in ultrathin single crystals of alpha-octithiophene (alph a-8T) is presented. For example, the gain narrowing of two narrow emis sion lines that appear when the crystals are pumped can be described i n the usual framework of stimulated emission. In contrast to dye-doped crystals, alpha-8T provides both the emitter and the optical cavity.