Directly driven source of multi-gigahertz, sub-picosecond optical pulses

Patent metadata

Field	Value
Publication number	US-9166355-B2
Application number	US-201214343706-A
Country	US
Kind code	B2
Filing date	Sep 12, 2012
Priority date	Sep 12, 2011
Publication date	Oct 20, 2015
Grant date	Oct 20, 2015

Abstract

A robust, compact optical pulse train source is described, with the capability of generating sub-picosecond micro-pulse sequences, which can be periodic as well as non-periodic, and at repetition rates tunable over decades of baseline frequencies, from MHz to multi-GHz regimes. The micro-pulses can be precisely controlled and formatted to be in the range of many ps in duration to as short as several fs in duration. The system output can be comprised of a continuous wave train of optical micro-pulses or can be programmed to provide gated bursts of macro-pulses, with each macro-pulse consisting of a specific number of micro-pulses or a single pulse picked from the higher frequency train at a repetition rate lower than the baseline frequency. These pulses could then be amplified in energy anywhere from the nJ to MJ range.

First claim

We claim:

1. An apparatus, comprising:
a continuous wave (CW) laser for providing a CW laser beam;
at least one electro-optic modulator for modulating said CW beam to produce a high repetition rate seed beam;
an optical amplifier capable of amplifying said seed beam to produce an amplified seed beam;
a spectral broadener for broadening the optical spectrum of said amplified seed beam to produce a spectrally broadened beam; and
a pre-compressor for temporally compressing said spectrally broadened beam to produce a train of bandwidth-limited short-duration output pulses.

2. The apparatus of claim 1 , further comprising:
at least one amplifier stage configured to amplify the power of said output pulses to produce amplified pulses; and
a pulse compressor configured to compress said amplified pulses to produce a train of short-pulse, high repetition-rate, high energy output pulses.

3. An apparatus, comprising:
a continuous wave (CW) laser for providing a CW laser beam;
at least one electro-optic modulator for modulating said CW beam to produce a high repetition rate seed beam;
an optical amplifier capable of amplifying said seed beam to produce an amplified seed beam; and
means for using self phase modulation of said amp 1 ified seed beam to produce a train of bandwidth-limited short-duration output pulses from said amplified seed beam, wherein said means comprises at least one:
a spectral broadener for broadening the optical spectrum of said amplified seed beam to produce a spectrally broadened beam; and
a pre-compressor for temporally compressing said spectrally broadened beam to produce said train of bandwidth-limited short-duration output pulses.

4. An apparatus, comprising:
a continuous wave (CW) laser for providing a CW laser beam;
at least one electro-optic modulator for modulating said CW beam to produce a high repetition rate seed beam;
an optical amplifier capable of amplifying said seed beam to produce an amplified seed beam;
a first spectral broadener for broadening the optical spectrum of said amplified seed beam to produce a first spectrally broadened beam;
a first pre-compressor for temporally compressing said first broadened beam to produce a first temporally compressed beam;
a second spectral broadener for broadening the optical spectrum of said first temporally compressed beam to produce a second spectrally broadened beam; and
a second pre-compressor for temporally compressing said second broadened beam to produce said train of bandwidth-limited short-duration output pulses.

5. The apparatus of claim 1 , wherein said at least one electro-optic modulator is configured for modulating said CW beam at a radio-frequency.

6. The apparatus of claim 1 , wherein said at least one electro-optic modulator is driven by a parabolic drive signal.

7. The apparatus of claim 1 , wherein said at least one electro-optic modulator comprises a first modulator and a second modulator, wherein said first modulator creates a very high frequency stream of micro-pulses from said CW beam, wherein said second modulator carves pulse bunches from said stream, and wherein said second modulator operates at a lower frequency than said first modulator and is gated for a predetermined interval of time to produce macro-pulses.

8. The apparatus of claim 6 , wherein said first modulator is driven at a frequency >2 GHz and said second modulator is driven at a frequency >10 KHz, and wherein said second modulator is gated to allow >100 pulses per macro-pulse.

9. The apparatus of claim 1 , wherein said optical amplifier comprises an optical fiber amplifier, wherein said spectral broadener comprises a nonlinear optical fiber and wherein said pre-compressor comprises a pair of dispersive elements.

10. The apparatus of claim 1 , wherein said spectral broadener comprises a nonlinear optical fiber selected to preferentially attenuate light that would otherwise be generated by nonlinear stimulated Raman scattering.

11. The apparatus of claim 1 , wherein said electro-optic modulator is driven by a parabolic drive signal selected from the group consisting of (i) periodic in time, (ii) aperiodic in time and (iii) arbitrary in time.

12. The apparatus of claim 9 , wherein an optical limiter is positioned between said fiber amplifier and said pulse broadener, wherein said optical. limiter is configured to produce substantially uniform intensity pulses in a plurality of pulses of said amplified seed beam.

13. The apparatus of claim 1 , wherein said CW laser is configured to provide at least one wavelength within a range within a range from 1000 nm to 2000 nm.

14. The apparatus of claim 1 , wherein said at least one electro-optic modulator is configured to produce a high repetition rate seed beam having a repetition rate of at least 2 GHz.

15. The apparatus of claim 1 , wherein said at least one electro-optic modulator is configured to produce a high repetition rate seed beam having a repetition rate within a range from 1 GHz to 100GHz.

16. The apparatus of claim 1 , wherein said short-pulse, high repetition-rate, high energy output pulses comprise a pulse duration within a range from 10 fs to 1 ps, a repetition rate within a range from 1 GHz to 100 GHz and energy within a range from 100 pJ to 1 μJ.

17. The apparatus of claim 1 , wherein said short-pulse, high repetition-rate, high energy output pulses comprise a pulse duration within a range from 10 fs to 1 ps, a repetition rate within a range from 1 GHz to 100 GHz and energy within a range from 1 μJ to 10 mJ.

18. A method, comprising:
providing a continuous wave (CW) laser beam from a CW laser;
modulating, with at least one electro-optic modulator, said CW beam to produce a high repetition rate seed beam;
amplifying, with an optical amplifier, said seed beam to produce an amplified seed beam;
broadening, with a spectral broadener, the optical spectrum of said amplified seed beam to produce a spectrally broadened beam; and
temporally compressing, with a pre-compressor, said spectrally broadened beam to produce a train of band width-limited short-duration output pulses.

19. The method of claim 18 , further comprising:
amplifying, with at least one amplifier stage, the power of said output pulses to produce amplified pulses; and
compressing, with a pulse compressor, said amplified pulses to produce a train of short-pulse, high repetition-rate, high energy output pulses.

20. A method, comprising:
providing a continuous wave (CW) laser beam from a CW laser;
modulating, with at least one electro-optic modulator, said CW bean to produce a high repetition rate seed beam;
amplifying, with an optical amplifier, said seed beam to produce an amplified seed beam; and
utilizing means for using self phase modulation of said amplified seed beam to produce a train of bandwidth-limited short-duration output pulses from said amplified seed beam, wherein said means comprises at least one of:
a spectral broadener for broadening the optical spectrum of said amplified seed beam to produce a spectrally broadened beam; and
a pre-compressor for temporally compressing said spectrally broadened beam to produce said train of bandwidth-limited short-duration output pulses.

21. A method, comprising:
providing a continuous wave (CW) laser beam from a CW laser;
modulating, with at least one electro-optic modulator, said CW beam to produce a high repetition rate seed beam;
amplifying, with an optical amplifier, said seed beam to produce an amplified seed beam; and
utilizing

Assignees

• Messerly Michael J
• Dawson Jay W
• Barty Christopher P J
• Gibson David J
• Prantil Matthew A
• Cormier Eric
• L Livermore Nat Security Llc

Inventors

• Messerly Michael J
• Dawson Jay W
• Barty Christopher P J
• Gibson David J
• Prantil Matthew A
• Cormier Eric

Classifications

• H01S3/06754

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

• H01S3/2383

  Parallel arrangements · CPC title

• H01S3/06758

  Tandem amplifiers · CPC title

• H01S3/0085 Primary

  Modulating the output, i.e. the laser beam is modulated outside the laser cavity · CPC title

• H01S3/10046

  Pulse repetition rate control (H01S3/11 takes precedence) · CPC title