Time-Resolved Impulsive Stimulated Raman Spectroscopy with Synchronized Triple Mode-Locked Lasers

Area of Science:

• Physical Chemistry
• Spectroscopy
• Photochemistry

Background:

• Understanding photochemical reaction dynamics requires real-time measurement of molecular electronic and vibrational structures.
• Time-resolved impulsive stimulated Raman spectroscopy (TR-ISRS) is a key technique for investigating structural changes in photoexcited molecules.

Purpose of the Study:

• To demonstrate the feasibility of femtosecond TR-ISRS using synchronized triple mode-locked lasers without external time-delay devices.
• To enable rapid data acquisition and wide dynamic range measurements for photochemical dynamics.

Main Methods:

• Utilized synchronized triple mode-locked lasers for femtosecond actinic pump, Raman pump, and Raman probe pulses.
• Achieved automatic scanning of delay times by independently controlling the three laser repetition rates.
• Measured fifth-order TR-ISRS signals.

Main Results:

• Successfully implemented femtosecond TR-ISRS with synchronized triple mode-locked lasers.
• Demonstrated rapid data acquisition and wide dynamic range measurement capabilities.
• Eliminated the need for conventional time-delay equipment.

Conclusions:

• The developed triple mode-locked laser-based TR-ISRS technique is effective for real-time monitoring of photochemical reaction dynamics.
• This technique is anticipated to be valuable for studying dynamics in condensed phases and biological systems.
• Offers a streamlined approach for advanced spectroscopic analysis.