APPLIED PHYSICS LETTERS 101, 153305 (2012).pdf

We report the improvement of the amplified spontaneous emission (ASE) performance in the
optically pumped symmetric thin film waveguide glass/indium-tin oxide (ITO)/SiO2/poly[2-
methoxy-5-(20-ethylhexyloxy)-1,4-phenylenevinylene]/SiO2/Al or Ag by optimizing the thickness
of SiO2 and replacing the Al electrode with Ag, where SiO2 acted as a spacer layer to prevent the
ASE at 620 nm from being destructed. The results show that the SiO2/Ag cladding reduced the
ASE threshold to 4 lJ/pulse compared with the SiO2/Al cladding, owing to the higher work
function and reflection rate as well as lower absorption loss of the Ag electrode. No
photoluminescence at 580 nm being observed makes it possible for an electric field to only
modulate the ASE at 620 nm in the device with the SiO2/Ag cladding. The electric-field quenching
of the ASE has been observed, which increases with the electric field. The field dependence of
ASE can be attributed to field-induced dissociation of photogenerated excitons in the polymer
waveguides.