Laser based frequency standards and their applications

Patent metadata

Field	Value
Publication number	US-10014653-B2
Application number	US-201514883018-A
Country	US
Kind code	B2
Filing date	Oct 14, 2015
Priority date	Oct 17, 2005
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same.

First claim

What is claimed is:

1. A frequency comb based optical source, comprising:
a passively modelocked waveguide oscillator operating at a pulse repetition frequency PRF and providing pulses with a corresponding pulse separation T=1/PRF, said waveguide oscillator comprising a dispersion compensated optical cavity, said optical cavity containing cavity components, wherein said dispersion of said dispersion compensated optical cavity is substantially lower than the dispersion of each of the cavity components; and
an optical distribution system disposed downstream from said passively mode locked waveguide oscillator and operably arranged for optical transmission of a time, frequency, or wavelength standard, said optical distribution system transmitting said time, frequency or wavelength standard to a remote location.

2. The frequency comb based optical source according claim 1 , further comprising one or more optical amplifiers.

3. The frequency com based optical source according claim 1 , further comprising stabilized fiber links.

4. The frequency comb based optical source according claim 1 , wherein said frequency comb based source is arranged as a portion of an optical clock.

5. The frequency comb based optical source according to claim 1 , said source configured such that said pulse repetition frequency PRF is characterized by the relationship:
RF=( f OPT ±f ceo ±f beat )/ l
where l is an integer representing the mode number of the frequency comb mode closest to f OPT , f OPT is the frequency of an optical reference, f ceo is the carrier envelope offset frequency, and f beat is the beat frequency between said comb line with said comb mode number 1 and an output of said optical reference,
wherein f ceo and f beat are locked to external RF references via phase-locked loops.

6. The frequency comb based optical source according to claim 1 , further configured to generate a low noise RF output at an output frequency, said RF output frequency being defined via a fixed relation to said optical reference frequency, f OPT , said carrier envelope offset frequency f ceo and said beat frequency f beat .

7. The frequency comb based optical source according to claim 1 , comprising a differential optical delay line constructed such that the pulse separation is decreased by a factor T/N, where N is an integer, with N−1 representing the number of stages in said differential optical delay line.

8. The frequency comb based optical source according to claim 1 , wherein an RF output signal is derived via direct photo-detection with a photodiode, said optical source operably arranged to generate the low noise RF output at an output frequency and to provide low noise operation via limiting excess noise generation in said photodiode and/or providing an output of said modelocked oscillator having a center wavelength at or near a wavelength of maximum sensitivity of said photodiode.

Assignees

• Imra America Inc

Inventors

• Hartl Ingmar
• Fermann Martin

Classifications

• H01S3/067

  Fibre lasers · CPC title

• G02F1/3558

  Poled materials, e.g. with periodic poling; Fabrication of domain inverted structures, e.g. for quasi-phase-matching [QPM] · CPC title

• G02F2203/56

  Frequency comb synthesizer · CPC title

• G02F1/365 Primary

  in an optical waveguide structure (G02F1/377, {G02F1/395} take precedence) · CPC title

• H01S2301/02

  ASE (amplified spontaneous emission), noise; Reduction thereof · CPC title