Dispersion managed fiber stretcher for high-energy short pulse femotosecond fiber laser system

Abstract

A fiber Chirped Pulse Amplification (CPA) laser system that includes a fiber mode-locking oscillator for generating a seed laser for projecting to a stretcher for generated a pulse-stretched laser for projecting to a multiple stage amplifier. The multiple stage amplifier further amplifying said laser for projecting to a compressor for compressing said laser to generate an output laser of an original pulse width. In this invention, pulse stretcher is implemented with a special dispersion management fiber that has a flat dispersion or a negative TOD (dispersion slope, or a slope of dispersion versus wavelength).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram for showing a fiber laser system implemented with pulse stretcher having a special dispersion management fiber that has a flat dispersion or a negative dispersion of this invention.

FIG. 2 is a fiber dispersion index profile over range of laser wavelengths for different types of fibers that may be implemented in the pulse stretcher of this invention for dispersion management and compensation.

FIG. 3 is a diagram of TOD grating as function of groove density.

FIG. 4 is a schematic diagram for illustrating the TOD compensation.

FIG. 5 shows curves for illustrating the pulse-shape improvement with TOD compensation accomplished by the new fibers implemented in this invention.

Claims

1. An ultra-fast fiber laser system comprising: a dispersion managed fiber stretcher in order to compensate a TOD (dispersion slope, or a slope of dispersion versus wavelength) of a grating compressor or in a regular fiber.

2. The ultra-fast fiber laser system of claim 1 wherein: said dispersion managed fiber stretcher comprising fibers having a refractive index profile different from a conventional fiber.

3. The ultra-fast fiber laser system of claim 1 wherein: said dispersion managed fiber stretcher comprising fibers having reflection index profile different from a conventional fiber with a depressed cladding structure.

4. The ultra-fast fiber laser system of claim 1 wherein: said dispersion managed fiber stretcher comprising a fiber of a flat dispersion.

5. The ultra-fast fiber laser system of claim 1 wherein: said dispersion managed fiber stretcher comprising a fiber of a negative TOD (dispersion slope, or a slope of dispersion versus wavelength).

6. The ultra-fast fiber laser system of claim 1 wherein: said dispersion managed fiber stretcher comprising a fiber of a design for managing/compensating a TOD with nonlinear effects through a self phase modulation (SPM) for providing different dispersions and dispersion slopes according to said TOD in said ultra-fast fiber laser system.

7. The ultra-fast fiber laser system of claim 1 wherein: said dispersion managed fiber stretcher comprising a fiber of a negative TOD (dispersion slope, or a slope of dispersion versus wavelength) with an absolute value about one to three times of a SM 28 fiber.

8. The ultra-fast fiber laser system of claim 1 wherein: said ultra-fast laser system operates at 1 μm region (1030-1100 nm).

9. The ultra-fast fiber laser system of claim 1 wherein: said ultra-fast laser system generates a laser with a pulse width from 10 ps to 10 fs.

10. The ultra-fast fiber laser system of claim 1 wherein: said ultra-fast laser system generates a laser with a laser energy from 1 nJ to 1 mJ.

11. A method for generating a laser by a fiber laser system comprising: chirping a laser pulse by a dispersion managed stretcher by implementing a fiber with a flat dispersion in said dispersion managed stretcher.

12. A method for generating a laser by a fiber laser system comprising: chirping a laser pulse by a dispersion managed stretcher by implementing a fiber with a negative TOD (dispersion slope, or a slope of dispersion versus wavelength) in said dispersion managed stretcher.

13. A fiber Chirped Pulse Amplification (CPA) laser system comprising: a fiber mode-locking oscillator for generating a seed laser for projecting to a stretcher for generating a pulse-stretched laser for projecting to a multiple stage amplifier for amplifying said laser for projecting to a compressor for compressing said laser to generate an output laser of an original pulse width wherein said pulse stretcher is implemented with a special dispersion management fiber having a flat dispersion or a negative TOD (dispersion slope, or a slope of dispersion versus wavelength).

14. The fiber CPA laser system of claim 13 wherein: said dispersion managed fiber stretcher comprising fibers having a refractive index profile different from a conventional fiber.

15. The fiber CPA laser system of claim 13 wherein: said dispersion managed fiber stretcher comprising fibers having reflection index profile different from a conventional fiber with a depressed cladding structure.

16. The fiber CPA laser system of claim 13 wherein: said dispersion managed fiber comprising a fiber of a flat dispersion.

17. The fiber CPA laser system of claim 13 wherein: said dispersion managed fiber comprising a fiber of a negative TOD (dispersion slope, or a slope of dispersion versus wavelength).

18. The fiber CPA laser system of claim 13 wherein: said dispersion managed fiber comprising a fiber of a design for managing/compensating a TOD with nonlinear effects through a self phase modulation (SPM) for providing different dispersions and dispersion slopes according to said TOD in said ultra-fast fiber laser system.

19. The fiber CPA laser system of claim 13 wherein: said dispersion managed fiber comprising a fiber of a negative TOD (dispersion slope, or a slope of dispersion versus wavelength) with an absolute value about one to three times of a SM 28 fiber.

20. The fiber CPA laser system of claim 13 wherein: said fiber CPA laser system operates at 1 μm region (1030-1100 nm).

21. The fiber CPA laser system of claim 13 wherein: said fiber CPA laser system generates a laser with a pulse width from 10 ps to 10 fs.