Researchers at Universitat Wurzburg in Germany have demonstrated InAs/GaInAs quantum-dot lasers that produce more than 5 mW of 1.3-µm light at room temperature. The lasers, which exhibited threshold currents of 6 mA, display continuous-wave operation to 85 °C and pulsed operation to 160 °C.

The team fabricated the devices using molecular beam epitaxy and a dots-in-a-well architecture. Three to eight layers of InAs dots lay in 10-nm-thick GaInAs wells separated by 40 to 50 nm of GaAs. A report of the devices appeared in the August issue of IEEE Photonics Technology Letters.