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Related Experiment Video

Updated: Jan 26, 2026

Absolute Quantum Yield Measurement of Powder Samples

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Published on: May 12, 2012

Demonstration of High-Power and Stable Single-Mode in a Quantum Cascade Laser Using Buried Sampled Grating.

Feng-Min Cheng^1,2, Jin-Chuan Zhang³, Dong-Bo Wang^1,2

¹Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.

Nanoscale Research Letters

|April 5, 2019

Summary

This study demonstrates a stable, single-mode quantum cascade laser with high output power. Optimized sampled gratings and precise facet control ensure reliable performance across varying conditions.

Keywords:

Distributed feedback Quantum cascade laser Sampled grating

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Area of Science:

Quantum optics
Semiconductor lasers
Mid-infrared photonics

Background:

Quantum cascade lasers (QCLs) are crucial for mid-infrared applications.
Achieving high-power, stable single-mode operation in QCLs remains a challenge.
Distributed feedback (DFB) structures are essential for single-mode emission.

Purpose of the Study:

To demonstrate a high-power, low-threshold, stable single-mode buried distributed feedback (DFB) quantum cascade laser (QCL).
To investigate the impact of sampled gratings and precise facet cleaving on laser performance.
To achieve reliable single-mode operation at approximately 4.87 μm.

Main Methods:

Incorporation of a sampled grating within the buried DFB QCL structure.
Precise control over the cleaved positions of the laser's end facets.
Optimization of the optical field distribution within the sampled grating structure.

Main Results:

Demonstrated stable single-mode operation at ~4.87 μm.
Achieved high continuous wave (CW) output powers of 948 mW (6-mm cavity) and 649 mW (4-mm cavity) at 20°C.
Enhanced single-mode yield through precise facet cleaving.
Observed stable single-mode emission and linear mode tuning without mode hopping under varying temperatures and injection currents.

Conclusions:

The developed sampled grating DFB QCL offers high-power, stable single-mode emission.
Optimized design and fabrication lead to enhanced laser performance and reliability.
This device is suitable for applications requiring stable mid-infrared single-mode light sources.