Distributed Bragg reflector quantum cascade lasers
AssigneeIrglare, LLC
InventorHong Shu
Life of this patent
Estimating the term…
Abstract
A QCL includes a gain region that generates radiation. An optical waveguide feeds the radiation back to the gain region. A first order and/or a second order Bragg reflector are formed in the optical waveguide. The first order Bragg reflector narrows a spectrum of the radiation. The second order Bragg reflector outcouples the radiation through a large facet.
Claims27
A device comprising a quantum cascade laser (QCL) having a crystal growth direction, the QCL comprising:
- a gain region that generates radiation, the gain region having a ridge width of at least 15 micrometers, the gain region having a thickness in the growth direction of not more than 1 μm;
- an optical waveguide that feeds the radiation back to the gain region;
- a first order Bragg reflector formed in the optical waveguide and coupled to the gain region in such a way that the first order Bragg reflector narrows a spectrum of the radiation;
- and
- a facet at an end of the gain region that emits the radiation from the QCL.
A device comprising a quantum cascade laser (QCL) having a crystal growth direction, the QCL comprising:
- a gain region that generates radiation, the gain region terminating at a facet that emits the radiation from the gain region;
- an optical waveguide that feeds the radiation back to the gain region;
- and
- a first order Bragg reflector formed in the optical waveguide and coupled to the gain region in such a way that the first order Bragg reflector narrows a spectrum of the radiation;
- the first order Bragg reflector and facet being spaced apart perpendicular to the crystal growth direction.
A device comprising a quantum cascade laser (QCL) having a crystal growth direction, the QCL comprising:
- a gain region that generates radiation, the gain region terminating at a facet that emits the radiation from the gain region;
- an optical waveguide that feeds the radiation back to the gain region;
- and
- a first order Bragg reflector formed in the optical waveguide and coupled to the gain region in such a way that the first order Bragg reflector narrows a spectrum of the radiation, the first order Bragg reflector having a resonance wavelength, the resonance wavelength being detuned from a peak gain wavelength of the QCL to reduce mode self-focusing, the first order Bragg reflector and facet being spaced apart perpendicular to the crystal growth direction.
A device comprising a quantum cascade laser (QCL) having a crystal growth direction, the QCL comprising:
- a gain region that generates radiation;
- an optical waveguide that feeds the radiation back to the gain region;
- a first order Bragg reflector formed in the optical waveguide and coupled to the gain region in such a way that the first order Bragg reflector narrows a spectrum of the radiation;
- a second order Bragg reflector formed in the optical waveguide, the first order Bragg reflector and second order Bragg reflector being formed on only a portion of the optical waveguide, thereby having a distributed Bragg reflector configuration;
- and
- a facet that emits the radiation from the QCL along the crystal growth direction.
Dependencies are inferred from the claim text.