High power sub-400 femtosecond MOPA with solid-state power amplifier

Patent metadata

Field	Value
Publication number	US-10535975-B2
Application number	US-201715692653-A
Country	US
Kind code	B2
Filing date	Aug 31, 2017
Priority date	Aug 31, 2017
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

Laser-apparatus includes a fiber-MOPA arranged to deliver amplified seed optical pulses having a wavelength of about 1043 nanometers to a multi-pass ytterbium-doped yttrium aluminum garnet solid-state optical amplifier for further amplification.

First claim

What is claimed is:

1. Laser apparatus, comprising:
a fiber-laser oscillator delivering optical pulses having a first pulse-duration, the pulses having a center-wavelength between 1038 nanometers and 1052 nanometers;
a pulse-stretcher arranged to stretch the duration of the optical pulses to a second pulse-duration longer than the first pulse-duration;
at least one fiber-amplifier arranged to amplify the stretched optical pulses;
a solid-state multi-pass amplifier including a gain-element made of ytterbium-doped yttrium aluminum garnet having a peak-gain wavelength of about 1030 nm, arranged to further amplify the amplified stretched optical pulses from the fiber-amplifier; and
a pulse-compressor arranged to reduce the duration of the further-amplified optical pulses from the solid-state multi-pass amplifier to a duration of less than about 400 femtoseconds.

2. The apparatus of claim 1 , wherein the center wavelength of the optical pulses from the fiber-laser oscillator is about 1043 nanometers.

3. The apparatus of claim 1 , wherein the center wavelength of the optical pulses from the fiber-laser oscillator is about 1048 nanometers.

4. The apparatus of claim 1 , wherein the gain-element of the solid-state multi-pass amplifier is in the form of a slab.

5. The apparatus of claim 4 , wherein the amplified stretched optical pulses being further amplified make less than about 12 passes through the slab gain-element.

6. The apparatus of claim 4 , wherein the slab gain-element has at least one un-pumped area that attenuates parasitic lasing at about 1030 nanometers.

7. The apparatus of claim 1 , wherein the amplified stretched optical pulses from the fiber-amplifier have a pulse energy to suppress parasitic lasing at about 1030 nanometers.

8. The apparatus of claim 1 , wherein the amplified stretched optical pulses from the fiber-amplifier have an average power of greater than about 20 Watts and the reduced-duration pulses from the pulse-compressor have an average power of greater than about 100 Watts.

9. The apparatus of claim 1 , further including a filter element located in the solid-state multi-pass amplifier that provides loss at about 1030 nanometers.

10. The apparatus of claim 9 , wherein the filtering element is a grating-compressor and a beam-block, the beam-block blocking 1030 nanometers in a spectrally dispersed beam within the grating-compressor.

11. The apparatus of claim 1 , wherein the reduced-duration pulses from the pulse-compressor have a duration of less than about 200 femtoseconds.

Assignees

• Coherent Inc

Inventors

• Starodoumov Andrei
• Hodgson Norman

Classifications

• H01S3/0941

  of a laser diode · CPC title

• H01S3/09415

  the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping · CPC title

• H01S3/1643

  YAG · CPC title

• H01S3/2341

  Four pass amplifiers · CPC title

• H01S3/06754

  Fibre amplifiers (H01S3/06708 takes precedence) · CPC title