Abstract
In this paper, the spectral properties of a conjugated polymer poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV) in benzene have been studied. The results showed that the fluorescence spectra of MEH-PPV under low concentrations had two peaks; the dominant one due to monomer was around 560 nm, and the shoulder one attributed to the excimer was around 600 nm. Under higher concentrations, it was found that there was only one band around 600 nm due to the excimeric state. By increasing the concentrations of MEH-PPV, it could be seen that there was a new band around 640nm. This band is being attributed to the double excimer. Under high power pulsed laser excitation, we observed amplified spontaneous emission (ASE) at 570 nm, 605 nm and 650 nm. These ASE peaks could arise from the monomer, excimer and double excimer states of the macromolecule respectively. To the best of our knowledge this is perhaps the first report on ASE from double excimer of the conjugated polymer, MEH-PPV in liquid solution. [DOI: http://dx.doi.org/10.2971/jeos.2013.13001]