Japanese researchers at Yokohama R&D Laboratories in Kanagawa and Fitel Photonics Laboratories in Chiba report in an upcoming issue of IEEE Photonics Technology Letters highly stable laser modules that employ a single thermoelectric cooler (TEC). The devices promise to reduce power consumption and costs as sources for telecom applications.

The new lasers incorporate etalon temperature data into a wavelength-locking feedback loop to compensate for drift. In experiments, a 20-mW, 1560.2-nm device exhibited a maximum wavelength drift of ±0.25 pm at case temperatures of -5 to 70 °C, corresponding to drift of 4.87 pm over a typical device's life span.