Searching for Evidence of Optical Rectification: Optically-Induced Nonlinear Photovoltage in a Capacitor Configuration

Thumbnail Image
Mirzaee, Somayeh
Nunzi, Jean-Michel
Nonlinear optical devices; Nonlinear optical materials; Nonlinear optics at surfaces; Photothermal effects
A current challenge in photonics is to design new versatile photodetectors based on optical rectification induced photo-voltage; these ones are more attractive than classical photodetectors because they do not rely on band to band transitions. Identification of the origin of the photovoltage detected under intense illumination can sometimes be confusing due to the competition between several nonlinear processes. Examples of such processes are optical rectification, multiphoton absorption, and photothermal heating, all of which may result in the detection of a DC photovoltage in a capacitor configuration. Herein, differences between the resulting photovoltage from these processes are analyzed, and techniques are proposed to distinguish between optical rectification-induced DC photovoltage and the photovoltage resulting from alternative effects.