Supercontinuum Generation With GHz Repetition Rate Femtosecond-Pulse Fiber-Amplified VECSELs

Abstract

Abstract-We report supercontinuum generation using a mode-locked VECSEL emitting 400-fs pulses at a 3-GHz repetition rate, amplified with a cascaded ytterbium-doped fiber amplifier system up to 40 W of average power. The pulses were then recompressed to their original duration via a high throughput transmission grating compressor, and used to generate supercontinuum in two samples of photonic crystal fiber (PCF); an all-normal dispersion PCF, and a PCF with a zero dispersion wavelength of 1040 nm, creating 20 dB spectral bandwidths of 200 nm and 280 nm respectively.

Saturated gain spectrum of VECSELs determined by transient measurement of lasing onset

“…Only relatively recently, however, have thermal management of the quantum well gain structure, and optical management of the intracavity pulse-shaping process, reached a level at which peak optical pulse powers in the kilowatt regime can be demonstrated [3,4]. The combination of intense femtosecond pulses with broadly tunable GHz repetition rates [5,6] may lend itself to a number of applications such as supercontinuum generation for frequency combs [7][8][9].…”

Ultrafast High-Repetition-Rate Waveguide Lasers

“…An APCVD-grown graphene layer was transferred to the upper surface of the waveguide and Q-switched output was obtained at average powers approaching 0.5 W [82]. An alternative approach to power scaling would be to adopt a master-oscillator-power-amplifier configuration, either using further high-power planar-waveguide amplifiers [83] or utilizing optical-fiber amplifiers [84].…”

High-power amplification of a femtosecond vertical external-cavity surface-emitting laser in an Yb:YAG waveguide

“…With fiber amplifiers average power levels above 200 W were generated [12]. The amplified signal was employed for the generation of supercontinuum [13,14] as well as for the first carrier-envelope offset (CEO) frequency detection of a VECSEL [15]. However, the long fiber results in a relatively large footprint of the system.…”