  We present a near IR photoresponse study of large area multi-walled carbon
nanotube/poly(3-hexylthiophene)-block-polystyrene polymer (MWNT/P3HT-b-PS)
nanocomposite films for different loading ratio of MWNT into the polymer
matrix. We show that the photocurrent strongly depends on the position of the
laser spot with maxiumum photocurrent occurring at the metal - film interface.
In addition, compared to the pure MWNT film, the photoresponse is much larger
in the MWNT/polymer composite films. The time constant for the photoresponse is
slow and varies between 0.6 and 1.2 seconds. We explain the photoresponse by
Schottky barrier modulation at the metal - film interface.
