PHOTOCONDUCTIVITY OF THE LADDER POLYMER BBL

The absorption and photoconduction properties of the ladder polymer po lybenzimidazo-benzoisoquinoline, BBL, are studied. The steady-state ph otoconductivity was measured as a function of photon energy, electric field, temperature, and chopper frequency. The photocurrent response a s a function of energy precedes the absorption and shows a broad tail around the band edge in contrast to the sharp absorption edge near 1.6 8 eV.