Disordered multiwalled carbon nanotube mat for light spot position detecting

Photovoltaic effects in a disordered multiwalled carbon nanotube mat/nickel heterostructure have been investigated. It is found that the photovoltage in the whole mat between two nickel electrodes under the irradiation of a 532-nm laser shows a single-valued function dependence on the light spot position, while it shows an almost linear dependence on light intensity. Based on the 'position effect', the prototype of the light spot position detector has been constructed for the applications of the disordered multiwalled carbon nanotubes in precision measurement.