A 75 MHz light source for femtosecond stimulated raman microscopy

Area of Science:

• Spectroscopy
• Microscopy
• Laser Physics

Background:

• Femtosecond stimulated Raman microscopy (FSRM) utilizes synchronized Raman probe and pump pulses to generate spectra from a sample's focal volume.
• Existing FSRM light sources face challenges in pulse synchronization and spectral characteristics.

Purpose of the Study:

• To present a novel, synchronized light source for FSRM.
• To characterize the spectral and temporal properties of the generated pump and probe pulses.
• To demonstrate the capability of simultaneous broadband Raman spectra recording using the novel light source.

Main Methods:

• An 8-fs laser operating at 75 MHz was used as the Raman probe.
• A Yb(3+)-based fiber amplifier generated the Raman pump light at 980 nm.
• The amplifier was seeded by the spectral wing of the 8-fs laser output to ensure pump-probe pulse synchronization.

Main Results:

• The spectral and temporal characteristics of the synchronized pump and probe pulses were successfully reported.
• Simultaneous recording of broadband Raman spectra was demonstrated, validating the light source's performance.
• The novel light source provides synchronized ultrashort pulses essential for high-resolution FSRM.

Conclusions:

• The developed light source is a significant advancement for femtosecond stimulated Raman microscopy.
• The synchronized pump and probe pulses enable efficient and simultaneous broadband Raman spectral acquisition.
• This technology has the potential to improve sensitivity and resolution in FSRM applications.