Low-temperature lasing action in a metal-backed monosubstituted polyacetylene

Within a metal-backed feedback structure, low-temperature laser action has been observed in a highly luminescent monosubstituted polyacetylene, poly (n - [(4′ -hexylcarbonyl-biphenyl-4-oxy)]-1-propyne}(PBP), at a low pump intensity of about 4 kW cm2. Sandwiched between a finely polished copper plate and a quartz plate, solid films of the polymer PBP begin to give off sharp line emission at 570 nm when the temperature drops below 200 K. Both the temperature and the pump intensity dependences of the sharp line emission are investigated. Our results suggest that low-temperature lowered threshold makes lasing feasible in PBP at a considerably low pumping intensity.