Controlling Quantum Interference between Virtual and Dipole Two-Photon Optical Excitation Pathways Using Phase-Shaped...

Area of Science:

• Physical Chemistry
• Quantum Optics
• Spectroscopy

Background:

• Two-photon excitation (TPE) involves virtual and dipole pathways, especially in non-centrosymmetric molecules.
• Controlling quantum interference between these pathways is crucial for optimizing TPE processes.

Purpose of the Study:

• To investigate the quantum control of TPE via interference between virtual and dipole pathways.
• To enhance two-photon-excited fluorescence using phase-shaped femtosecond laser pulses.

Main Methods:

• Utilized phase-shaped femtosecond laser pulses to control quantum interference.
• Measured two-photon-excited fluorescence of photobase FR0-SB in methanol.
• Performed simulations accounting for pathway responses and pulse shaping effects.

Main Results:

• Achieved fluorescence enhancements up to 1.75 by controlling quantum interference.
• Simulations showed good agreement with experimental measurements.
• Demonstrated effective quantum control of TPE in the condensed phase.

Conclusions:

• Quantum control of TPE pathways can significantly enhance fluorescence signals.
• Potential applications include improved two-photon microscopy and novel spectroscopic methods.
• Findings highlight the importance of controlling optical excitation pathways for advanced photonic applications.