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Updated: May 25, 2026
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Effect of emitter number on quantum cascade laser monolithic phased array
G M de Naurois1, M Carras, G Maisons
1III-V Lab, Campus Polytechnique, Palaiseau, France. guy‐mael.denaurois@3-5lab.fr
Optics Letters
|February 3, 2012
Summary
Researchers analyzed mid-infrared quantum cascade laser arrays, achieving room-temperature lasing at 8.4 μm. The study demonstrates highly coherent emission from up to 32 emitters using evanescent coupling.
Area of Science:
- Optics and Photonics
- Semiconductor Lasers
- Quantum Cascade Devices
Background:
- Quantum cascade lasers (QCLs) are crucial for mid-infrared (mid-IR) applications.
- Developing high-power, coherent sources in the mid-IR remains a significant challenge.
- Spatial arrays offer a pathway to enhance output power and beam quality.
Purpose of the Study:
- To optically analyze spatial single-mode monolithic quantum cascade laser arrays.
- To investigate phase-locking mechanisms and emission characteristics.
- To demonstrate room-temperature operation of multi-emitter QCL arrays.
Main Methods:
- Fabrication of subwavelength parallel microstripe waveguides buried in InP:Fe.
- Phase locking of emitters via evanescent coupling.
- Optical analysis including near-field and far-field measurements.
- Comparison with standard optical simulations.
Main Results:
- Room-temperature lasing achieved at a wavelength of 8.4 μm.
- Detailed characterization of near- and far-field emission patterns for arrays up to 32 emitters.
- Experimental demonstration of 100% coherent emission.
- Excellent agreement between experimental results and optical simulations.
Conclusions:
- Spatial single-mode monolithic quantum cascade laser arrays can achieve high coherence.
- Evanescent coupling is an effective method for phase-locking multiple emitters.
- These arrays represent a promising technology for high-power, coherent mid-IR sources.
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