Compression of optical pulses chirped by self-phase modulation in fibers

TLDR

The use of self‑phase modulation in a single‑mode fiber to chirp an optical pulse, followed by compression with a grating‑pair compressor, has proven to be a practical method for generating pulses as short as 30 fsec. The study presents a theoretical analysis of this chirping and compression process. The results are expressed in normalized units, enabling scaling to various experimental conditions and facilitating the determination of optimal fiber length and compressor settings for any given input pulse. Numerical analysis shows that, for input pulses shorter than about 100 psec and energies of a few nanojoules, the technique can compress pulses to femtosecond widths, with compression quality and achievable pulse width depending on fiber length and input intensity.

Abstract

The use of self-phase modulation in a single-mode fiber to chirp an optical pulse, which is then compressed with a grating-pair compressor, has been shown to be a practical technique for the production of optical pulses at least as short as 30 fsec. We report the results of a theoretical analysis of this process. Numerical results are presented for the achievable compression and compressed pulse quality as functions of fiber length and input pulse intensity. These results are given in normalized units such that they can be scaled to describe a wide variety of experimental situations and can be used to determine the optimum fiber length and compressor parameters for any given input pulse. Specific numerical examples are presented that suggest that the technique will generally be useful for input pulses shorter than about 100 psec. For energies of a few nanojoules per pulse, the compressed pulse widths will typically be in the femtosecond regime.