Systematic control of nonlinear optical processes using optimally shaped femtosecond pulses

Area of Science:

• Nonlinear Optics
• Quantum Control
• Laser Physics

Background:

• Nonlinear optical processes are governed by the electric field of light.
• Understanding laser-molecule interactions is crucial for controlling quantum phenomena.
• Femtosecond laser pulse shaping offers a pathway to manipulate these interactions.

Purpose of the Study:

• To review experimental efforts in controlling multiphoton transitions using shaped femtosecond laser pulses.
• To elucidate the effect of phase on nonlinear optical laser-molecule interactions.
• To explore applications of pulse shaping and coherent control in nonlinear optics.

Main Methods:

• Analysis of nonlinear optical processes based on Taylor expansion of phase in the frequency domain.
• Experimental investigation of binary phase shaping (BPS) for controlling multiphoton transitions.
• Systematic study of laser-molecule interactions using shaped femtosecond pulses.

Main Results:

• Nonlinear optical processes are influenced by second- and higher-order phase terms.
• Binary phase shaping (BPS) demonstrates superior control over multiphoton processes compared to other methods.
• Cooperative action of all frequencies within a laser pulse bandwidth dictates transition outcomes.

Conclusions:

• Arbitrary phase variation can lead to redundancy, complicating optimization experiments.
• BPS enables maximum constructive or destructive interference by using only two phase values (0 and pi).
• Pulse shaping provides powerful tools for controlling nonlinear optical phenomena, with significant current and future applications.