A team from Université Montpellier II in Montpellier, France, Laboratoire Central de Recherche in Orsay, France, and Université Ibnou Zohr in Agadir, Morocco, have described the production of high-temperature quantum-well lasers that display continuous-wave emission from 2.2 to 2.4 µm. The report, which will appear in an issue of Electronics Letters, suggests that the lasers are particularly suited to monitoring trace atmospheric levels of CO, CH4, NO2 and HCOH. The GaInSbAs/GaAlSbAs lasers exhibit single longitudinal mode emission of 2.26 µm at room temperature and 2.43 µm at 124 °C. Their output is 45 mW at 22 °C and exceeds 10 mW at 100 °C.