Computing by Non-linear Optical Molecular Response

Non-linear optical spectroscopies probe the dynamics of optically active molecular systems interacting with a sequence of laser pulses. By encoding logical inputs into the allowed optical transitions, quantum dynamics of populations and coherences implement logic processing in parallel and a macroscopically readable output is obtained from the spectroscopic response. The resulting hardware-based logic improves the potentialities of molecular sized devices for computing applications. We introduce the basic concepts of this molecular computing scheme and discuss its strengths and drawbacks with respect to several performance indicators.