Quantum Interband and Cascade Lasers

Over 16 years have passed since the Bell Labs group headed by Federico Capasso first demonstrated the quantum cascade laser (QCL). The intervening interval has seen the QCL evolve from a barely functional scientific curiosity into a powerful technology poised to offer new capabilities to a broad spectrum of real-world applications. In assembling this special section of Optical Engineering, our dual goals have been to provide a snapshot of the cascade laser field in its adolescence, and to familiarize a wider audience of optical engineers with the far-reaching practical potential of these unique IR sources. Contents: Special Section Guest Editorial: Quantum and Interband Cascade Lasers
• Highperformance midinfrared quantum cascade lasers
• High-performance InP-based midinfrared quantum cascade lasers at Northwestern University
• Reliabilityof4.6-µm quantum cascade lasers under continuous-wave room-temperature operation
• Progress in high-performance quantum cascade lasers
• Quantum cascade lasers: highpower emission and single-mode operation in the long-wave infrared (? 6 µm)
• Nonlinear gain behavior in injectorless quantum cascade lasers
• Electron leakage and its suppression via deep-well structures in 4.5- to 5.0-µm-emitting quantum cascade lasers
• High-performance quantum cascade lasers in the 7.3- to 7.8-µm wavelength band using strained active regions
• Transport and gain in a quantum cascade laser: model and equivalent circuit
• Power scaling of quantum cascade lasers via multiemitter beam combining
• Loss-reduction in midinfrared photonic crystal quantum cascade lasers using metallic waveguides
• Strategies toward the realization of two-dimensional broadband and coherent quantum cascade ring laser arrays
• Nonlinear coupling of transverse modes in quantum cascade lasers
• Heat transport in terahertz quantum cascade lasers
• Ridge-width dependence of midinfrared interband cascade laser characteristics
• Shortened injector interband cascade lasers for 3.3- to 3.6-µm emission
• Interband cascade laser–based sensor for ambient CH4
• Thermoelectrically cooled interband cascade laser for field measurements
• Utilizing broad gain bandwidth in quantum cascade devices
• Applications of midinfrared quantum cascade lasers to spectroscopy
• Quantum cascade lasers for high-resolution spectroscopy
• Current status of midinfrared quantum and interband cascade lasers for clinical breath analysis
• Application of quantum cascade lasers to high-precision atmospheric trace gas measurements
• Quantum cascade laser open-path system for remote sensing of trace gases in Beijing, China
• Use of quantum cascade lasers for detection of explosives: progress and challenges
• Imaging standoff detection of explosives using widely tunable midinfrared quantum cascade lasers