Long Wavelength (λ &gt; 17 µm) Distributed Feedback Quantum Cascade Lasers Operating in a Continuous Wave at Room Temperature

Hoang Nguyen Van,Roland Teissier,Michael Bahriz,Zeineb Loghmari,Hadrien Philip,Alexei Baranov

doi:10.3390/photonics6010031

Abstract

The extension of the available spectral range covered by quantum cascade lasers (QCL) would allow one to address new molecular spectroscopy applications, in particular in the long wavelength domain of the mid-infrared. We report in this paper the realization of distributed feedback (DFB) QCLs, made of InAs and AlSb, that demonstrated a continuous wave (CW) and a single mode emission at a wavelength of 17.7 µm, with output powers in the mW range. This is the longest wavelength for DFB QCLs, and for any QCLs or semiconductor lasers in general, operating in a CW at room temperature.

Highlights

Quantum cascade lasers (QCLs) have become a very efficient and mature light source for the midto far-infrared [1]
The long wavelength domain above 10 μm is much less explored as compared to the 4–10 μm range since it is difficult to obtain high performance sources when the wavelength is increased
We report significant progress with these lasers, roomatemperature at a wavelength of 17.7 with record long wavelength operation ofμm

Summary

Introduction

Quantum cascade lasers (QCLs) have become a very efficient and mature light source for the midto far-infrared [1]. The long wavelength domain above 10 μm is much less explored as compared to the 4–10 μm range since it is difficult to obtain high performance sources when the wavelength is increased. It is of interest for many applications such as the detection of C2 H2 and aromatics such as benzene, toluene, and xylenes (BTEX). Wavelength range of the mid-infrared been long explored in the early of QCLs, experiments are other applications that requirehas suitable wavelength laser years sources. DFB QCLs in a continuous wave at room temperature at a wavelength of 17.7 μm

Materials and Methods

Discussion

Conclusions