Abstract

Traditional methods of femtosecond pulse compression that use optical fiber as the bandwidth generating element are restricted in energy to a few nanojoules of compressed output owing to fiber damage thresholds. Although recent efforts¹ have succeeded in compressing amplified femtosecond pulses to <20 fs while maintaining μJ energies, each is limited in application by either low repetition rate or lack of wavelength selectivity. Here we present a novel pulse compression technique that utilizes the self-trapping and stable propagation of bright 2-D spatial solitons² in bulk nonlinear media. The self-phase modulation that accompanies soliton propagation provides sufficient bandwidth for compression, accomplished with a grating pair. Starting with 80-fs 620-nm 10-μJ pulses obtained from a colliding-pulse mode-locked ring dye laser amplified with a copper vapor laser pumped amplifier, we have achieved 19-fs 0.6-μJ pulses at a repetition rate of 8.6 kHz. Unlike alternative methods, spatial soliton pulse compression can be applied over a wide wavelength and energy range and can be used with high repetition rate amplifier systems. In addition, applications to the production of high repetition rate (>10 THz) pulse trains are discussed.

© 1991 Optical Society of America