Optical feedback-based repetitive frequency adjustable optical frequency comb

Patent metadata

Field	Value
Publication number	US-10901247-B2
Application number	US-201816315114-A
Country	US
Kind code	B2
Filing date	Jan 1, 2018
Priority date	Dec 5, 2016
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

The present invention provides a repetition frequency-tunable optical frequency comb generated by basis of optical feedback. The optical frequency comb comprises a single-frequency laser resonant cavity, a wavelength division multiplexer, a single-mode semiconductor pump light source, an optical circulator, a first optical fiber coupler, a second optical fiber coupler, a photoelectric detector, a highly-stable signal source, an error signal processing system, a laser frequency modulation device and a tunable laser-delay module. The present invention performs delay-time processing to the single-frequency laser by the tunable laser-delay module, and achieves an optical feedback by the optical circulator for injecting to the resonant cavity, generating a series of tunable laser longitudinal modes with equal frequency space. Meanwhile, in combination with the highly-stable signal source, the error signal processing system and the laser frequency modulation device, a laser frequency lock is achieved, and the laser frequency comb is generated. The invention obtains a repetition frequency-tunable laser frequency comb with a simple and practical method, having an extensive application prospect and huge application value in fields such as optical fiber sensing and spectroscopy of atom and molecule.

First claim

What is claimed:

1. A repetition frequency-tunable optical frequency comb generated by basis of optical feedback, characterized in that, the repetition frequency-tunable optical frequency comb comprises a single-frequency laser resonant cavity ( 1 ), a wavelength division multiplexer ( 2 ), a single-mode semiconductor pump light source ( 3 ), an optical circulator ( 4 ), a first optical fiber coupler ( 5 ), a second optical fiber coupler ( 6 ), a photoelectric detector ( 7 ), a highly-stable signal source ( 8 ), an error signal processing system ( 9 ), a laser frequency modulation device ( 10 ) and a tunable laser-delay module ( 11 ); structural relationships between each components are as follows: the single-frequency laser resonant cavity ( 1 ) being connected with a common port of the wavelength division multiplexer ( 2 ), a pump port of the wavelength division multiplexer ( 2 ) being connected with the single-mode semiconductor pump light source ( 3 ), a signal port of the wavelength division multiplexer ( 2 ) being connected with a port 2 of the optical circulator ( 4 ), an input port of the first optical fiber coupler ( 5 ) being connected with a port 3 of the optical circulator ( 4 ), one output port of the first optical fiber coupler ( 5 ) being connected with an input port of the second optical fiber coupler ( 6 ), an input port of the laser frequency modulation device ( 10 ) being connected with the other output port of the first optical fiber coupler ( 5 ), the tunable laser-delay module ( 11 ) being respectively connected with an output port of the laser frequency modulation device ( 10 ) and a port 1 of the optical circulator ( 4 ), one output port of the second optical fiber coupler ( 6 ) serving as an output of the optical frequency comb, an input port of the photoelectric detector ( 7 ) being connected with the other output port of the second optical fiber coupler ( 6 ), the highly-stable signal source ( 8 ) and an output port of photoelectric detector ( 7 ) being simultaneously connected with the error signal processing system ( 9 ), and an output port of the error signal processing system ( 9 ) being connected with a control port of the laser frequency modulation device ( 10 ).

2. The repetition frequency-tunable optical frequency comb generated by basis of optical feedback according to claim 1 , wherein the repetition frequency is less than 10 MHz.

3. The repetition frequency-tunable optical frequency comb generated by basis of optical feedback according to claim 1 , wherein an output of the single-frequency laser resonant cavity ( 1 ) is a single-frequency laser which is output with any wavelength, continuous single frequency and tunable frequency.

4. The repetition frequency-tunable optical frequency comb generated by basis of optical feedback according to claim 1 , wherein the highly-stable signal source ( 8 ) comprises a crystal oscillator, a signal generator or an atomic clock.

5. The repetition frequency-tunable optical frequency comb generated by basis of optical feedback according to claim 1 , wherein the laser frequency modulation device ( 10 ) comprises an optical fiber stretcher, an acoustic optical modulator, an electro-optic modulator or a magneto-optic modulator.

6. The repetition frequency-tunable optical frequency comb generated by basis of optical feedback according to claim 1 , wherein the tunable laser-delay module ( 11 ) comprises an optical fiber delay line or a high-reflectivity laser cavity.

7. The repetition frequency-tunable optical frequency comb generated by basis of optical feedback according to claim 1 , wherein after an output laser of the single-frequency laser resonant cavity ( 1 ) goes through the tunable laser-delay module ( 11 ), an optical feedback is achieved through the optical circulator ( 4 ) and the output laser is injected to the single-frequency laser resonant cavity ( 1 ), to generate a laser longitudinal mode with equal frequency space; and meanwhile in combination with the highly-stable signal source ( 8 ), the error signal processing system ( 9 ) and the laser frequency modulation device ( 10 ), a laser frequency lock is achieved, and a laser frequency comb is generated.

Assignees

• Univ South China Tech

Inventors

• Xu Shanhui
• Zhao Qilai
• Yang Zhongmin
• Feng Zhouming
• Yang Changsheng

Classifications

• H01S3/1106

  Mode locking · CPC title

• H01S3/0912 Primary

  Electronics or drivers for the pump source, i.e. details of drivers or circuitry specific for laser pumping (laser diode drivers H01S5/042) · CPC title

• H01S3/0933

  of a semiconductor, e.g. light emitting diode · CPC title

• H01S3/067

  Fibre lasers · CPC title

• H01S3/06791

  Fibre ring lasers (fibre laser gyrometers G01C19/72) · CPC title