Porphyrin-Tape/C60 Organic Photodetectors with 6.5% External Quantum Efficiency in the Near Infrared

Several porphyrin-dimer tapelike molecule/C-60 heterojunction detectors are investigated. Their extended it-electron systems provide photovoltaic response into the near infrared, with an external quantum efficiency of up to 6.5% at a wavelength of lambda = 1350 nm. Additionally, a specific detectivity of D* = 1.6 x 10(11) Jones at lambda = 1090 nm, and (2.3 +/- 0.1) x 10(10) Jones at lambda = 1350 nm are detected. The optical response time of the detectors is resistance capacitance limited at 1.87 +/- 0.03 ns.