Green and Ultraviolet Pulse Generation with a Compact, Fiber Laser, Chirped-Pulse Amplification System for Aerosol Fluorescence Measurements
Abstract
We use a compact chirped-pulse amplified system to harmonically generate ultra-short pulses for aerosol fluorescence measurements. The seed laser is a compact, all-normal dispersion, mode-locked Yb-doped fiber laser with a 1050-nm center wavelength operating at 41 MHz. Average powers of more than 1.2 W at 525 nm and 350 mW at 262 nm are generated high-dispersion fiber, amplified by a high-power, large-mode area fiber amplifier, and recompressed using a chirped volume holographic Bragg grating. The resulting high-peak-power pulse allow for highly efficient harmonic generation. We also demonstrate, for the first time to our knowledge, the use of a mode-locked ultra-violet source to excite individual biological particles and other collaboration particles in an inlet air flow as they pass through an optical chamber. The repetition rate is ideal for bio-fluorescence measurements as it allows faster sampling rates as well as the higher peak powers as compared to previously demonstrated Q-switched systems while maintaining a pulse period that is longer than the fluorescence recovery time. Thus, the fluorescence excitation can be considered to be quasi-continuous and required no external synchronization and triggering.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2010
- Accession Number
- ADA534782
Entities
People
- J.W. Lou
- Jay D. Eversole
- Marc Currie
- Vasanthi Sivaprakasam
Organizations
- United States Naval Research Laboratory