A compact packaging module for direct liquid cooling of roomtemperature quantum cascade lasers is implemented. The light was coupled out of the hermetically sealed package through a mid-infrared fibre epoxy-bonded to the laser. The threshold current reduces by 10%, compared to convectional substrate-side cooled lasers when using low boiling temperature (boiling point (b.p.)1⁄4 34 C) 3M HFE7000 ...

We propose a self-consistent method for the analysis of granular materials at terahertz (THz) frequencies using a quantum cascade laser. The method is designed for signals acquired from a laser feedback interferometer, and applied to non-contact reflection-mode sensing. Our technique is demonstrated using three plastic explosives, achieving good agreement with reference measurements obtained by...

Broad-area quantum cascade lasers with high output powers are highly desirable sources for various applications including infrared countermeasures. However, such structures suffer from strongly deteriorated beam quality due to multimode behavior, diffraction of light and self-focusing. Quantum cascade lasers presenting high performances in terms of power and heat-load dissipation are reported a...

Submitted for the MAR08 Meeting of The American Physical Society Compact Four-Wavelength Quantum Cascade Laser Source for Multi-Wavelength Spectroscopic Systems FATIMA TOOR, SCOTT HOWARD, CLAIRE GMACHL, Princeton University — Quantum cascade laser (QCL) technology in the mid-infrared wavelength range has great potential for applications in environmental trace gas sensing. QCL-based spectroscopi...

In the last decade quantum cascade lasers (QCLs) have become the most widely used source of mid-infrared radiation, finding large scale applications because of their wide tunability and overall high performance. However far-infrared (terahertz) QCLs have lagged behind in terms of performance and impact due to the inability so far of achieving room temperature operation. Here we review recent re...

The temperature dependence of coherent carrier transport in quantum cascade lasers (QCLs) is studied in this paper. It was found that coherent carrier transport in QCLs decreases as the temperature increases because the coherence between the injector and active region energy levels decays at a faster rate with increasing temperature. Calculations show that the coherence time decreases by at lea...

The semiconductor band gap of the individual layers of quantum cascade lasers has no infl uence on the emission wavelength. This offers the opportunity to develop lasers in the mid (3–30 μm) and far infrared (30– 500 μm) spectral region. The far infrared region is also known as the terahertz region (0.6–10 THz). Already theoretically predicted in 1971 [1], QCLs had not been realized until 1994 ...