An extended cavity diode-pumped femtosecond Yb: KGW laser for applications in optical DNA sensor technology based on fluorescence lifetime measurements

A reliable and power-scalable extended cavity diode-pumped passively mode-locked Yb:KGW laser generating similar to 200 fs long pulses at a repetition rate of 15 MHz was developed and characterized. The laser delivered up to 150 mW of average power at fundamental wavelength of 1040 nm, corresponding to a pulse energy of 10 nJ. The laser radiation was frequency-doubled in a single pass configuration within a nonlinear BIBO crystal to produce femtosecond green radiation at 520 nm with peak power of similar to 200 W. The generated second harmonic served as an excitation source for an optical DNA biosensor based on fluorescence lifetime measurements obtained using the time-correlated single photon counting technique. (c) 2006 Optical Society of America.