Tunable laser system and amplifier using a noble gas-filled hollow-core fiber waveguide

Patent metadata

Field	Value
Publication number	US-10243319-B1
Application number	US-201816030085-A
Country	US
Kind code	B1
Filing date	Jul 9, 2018
Priority date	Jul 9, 2018
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

An optical system including a laser system for generating a plurality of coaxial laser beams. The laser beams are combined by the laser system for generating at least two different frequency components. One or more hollow core photonic crystal fibers each filled with a noble gas receive the coaxial laser beams from the laser system and generate an idler emission having an idler frequency component according to four-wave mixing of the at least two different frequency components in the one or more hollow core photonic crystal fibers. A control system is configured to control a gas pressure of the one or more hollow core photonic crystal fibers for controlling the idler frequency component of the idler emission.

First claim

The invention claimed is:

1. An optical system comprising:
a laser system including a plurality of lasers for generating a plurality of coaxial laser beams having at least two different frequency components;
one or more hollow core photonic crystal fibers each filled with a noble gas for receiving the plurality of coaxial laser beams from the laser system and generating an idler emission having an idler frequency component according to four-wave mixing of the at least two different frequency components in the one or more hollow core photonic crystal fibers; and
a control system configured to control a gas pressure of the one or more hollow core photonic crystal fibers for controlling the idler frequency component of the idler emission.

2. The optical system of claim 1 wherein the control system is further configured to control a gas temperature of the one or more hollow core photonic crystal fibers for tuning of the idler frequency component of the idler emission.

3. The optical system of claim 2 wherein the control system is configured to vary the gas temperature of the one or more hollow core photonic crystal fibers between about 273K to about 400K.

4. The optical system of claim 1 wherein the plurality of lasers includes a signal laser for generating a signal laser beam having a signal frequency component, the control system being further configured to tune the signal frequency component for tuning of the idler frequency component of the idler emission.

5. The optical system of claim 1 wherein the at least two different frequency components of the plurality of coaxial laser beams generated by the laser system each have a wavelength of greater than 0 microns but less than about 2 microns and the idler frequency component includes a wavelength greater than 2 microns.

6. The optical system of claim 1 wherein:
the plurality of lasers consists of a signal laser for generating a signal laser beam having a signal frequency component having a wavelength of about 0.5 microns to about 2 microns and a pump laser for generating a pump laser beam having a pump frequency component having a wavelength of about 1 micron to about 2 microns,
the wavelength of the pump frequency component being greater than the wavelength of the signal frequency component, and
the idler frequency component having a wavelength greater than 2 microns.

7. The optical system of claim 1 wherein:
the plurality of lasers includes a signal laser for generating a signal laser beam having a signal frequency component having a wavelength of about 0.5 microns to about 2 microns and a plurality of pump lasers each for generating a pump laser beam having a pump frequency component having a wavelength of about 1 micron to about 2 microns,
each of the wavelengths of the pump frequency components being greater than the wavelength of the signal frequency component, and
the idler frequency component has a wavelength greater than 2 microns.

8. The optical system of claim 1 , wherein the one or more hollow core photonic crystal fibers each include a diameter of about 5 microns to about 20 microns.

9. The optical system of claim 1 wherein the one or more hollow core photonic crystal fibers are disposed in a controlled environment, and the control system controls the gas pressure of the fibers by controlling a gas pressure of the controlled environment.

10. The optical system of claim 9 wherein the one or more hollow core photonic crystal fibers include micro-holes in an outer surface of the fibers for facilitating control of the gas pressure of the one or more hollow core photonic crystal fibers.

11. An optical system comprising:
a laser system including a signal laser for generating a signal laser beam having a signal frequency component and one or more pump lasers each for generating a pump laser beam having a pump frequency component, the signal laser beam and the one or more pump laser beams being combined by the laser system for generating at least two coaxial laser beams having different frequency components;
one or more hollow core photonic crystal fibers each filled with a noble gas for receiving the at least two coaxial laser beams from the laser system and generating an idler emission having an idler frequency component according to four-wave mixing of the at least two coaxial laser beams in the one or more hollow core photonic crystal fibers; and
a control system configured to control a gas pressure and a gas temperature of the one or more hollow core photonic crystal fibers for controlling the idler frequency component of the idler emission.

12. The optical system of claim 11 wherein the gas pressure is controlled for coarse tuning of the idler frequency component and the gas temperature is controlled for fine tuning of the idler frequency component.

13. The optical system of claim 12 wherein the control system is operable to vary the gas pressure of the one or more hollow core photonic crystal fibers between about 1 atm to about 200 atm for coarse tuning and operable to vary the gas temperature of the one or more hollow core photonic crystal fibers between about 273K to about 400K for fine tuning.

14. The optical system of claim 11 wherein the control system is further configured to tune the signal frequency component for tuning of the idler frequency component of the idler emission.

15. The optical system of claim 11 wherein:
the laser system consists of the signal laser and a pump laser,
the signal frequency component of the signal laser includes a wavelength of about 0.5 microns to about 2 microns and the pump frequency component of the pump laser includes a wavelength of about 1 micron to about 2 microns,
the wavelength of the pump frequency component is greater than the wavelength of the signal frequency component, and
the idler frequency component has a wavelength greater than 2 microns.

16. The optical system of claim 11 wherein:
the laser system includes at least two pump lasers,
the signal frequency component of the signal laser includes a wavelength of about 0.5 microns to about 2 microns and the pump frequency component of each of the at least two pump lasers includes a wavelength of about 1 micron to about 2 microns,
each of the wavelengths of the pump frequency components being greater than the wavelength of the signal frequency component, and
the idler frequency component having a wavelength greater than 2 microns.

17. A method for producing a tunable idler emission having a wavelength greater than about 2 microns, the method comprising:
providing a laser system including a signal laser for generating a signal laser beam having a signal frequency component and one or more pump lasers each for generating a pump laser beam having a pump frequency component, the signal laser beam and the one or more pump laser beams being combined by the laser system for generating at least two coaxial laser beams having different frequency components;
transmitting the at least two coaxial laser beams through one or more hollow core photonic crystal fibers each filled with one or more noble gases to generate an idler emission having an idler frequency component according to four-wave mixing of the at least two coaxial laser beams;
providing a control system configured to control a gas pressure and a gas temperature of the one or more hollow core photonic crystal fibers and tune the signal component of the signal laser beam; and
tuning the idler frequency component of the idler emission by varying one or more of the gas pressure of the one or more hollow core photonic crystal fibers, the ga

Assignees

• Us Air Force

Inventors

• Keyser Christian K
• Welsh Chad M

Classifications

• H01S3/094003

  the pumped medium being a fibre · CPC title

• H01S3/036

  Means for obtaining or maintaining the desired gas pressure within the tube, e.g. by gettering, replenishing; Means for circulating the gas, e.g. for equalising the pressure within the tube {(H01S3/031 takes precedence)} · CPC title

• H01S3/1317 Primary

  by controlling the temperature · CPC title

• H01S3/0092 Primary

  Nonlinear frequency conversion, e.g. second harmonic generation [SHG] or sum- or difference-frequency generation outside the laser cavity (nonlinear frequency conversion per se G02F1/35) · CPC title

• H01S3/06741

  Photonic crystal fibre, i.e. the fibre having a photonic bandgap · CPC title