CYLINDRICAL MICROLASERS AND LIGHT-EMITTING DEVICES FROM CONDUCTING POLYMERS

Substantially improved, photopumped polymer lasers are demonstrated us ing microrings and microdisks of various diameters D ranging from 5 to 200 mu m. Various cavity-dependent laser modes were observed, which f or D<10 mu m were dominated by a single longitudinal mode with linewid th of less than 1 Angstrom. These microlasers were also characterized by Q of order 5000, low threshold excitation energy of order 100 pJ/pu lse for pulse duration ranging from 100 ps to sub-mu s, and an abrupt increase in the emission directionality and polarization degree. Light emitting diodes with cylindrical geometry, fully compatible with thes e microlasers are also demonstrated. (C) 1998 American Institute of Ph ysics.