Fig. 1: In-plane photovoltage stimulated by scanning a light beam.
From: Kinetic photovoltage along semiconductor-water interfaces

a Schematic illustrating the device structure. In-plane voltage signal across two terminals of a silicon strip in water was recorded while scanning a light beam. b Velocity profile of a light beam moving on a p-type Si strip (bottom, black) and the corresponding voltage signal (top, red).