Abstract:

We report on the demonstration of an array of master-oscillator power-amplifier quantum cascade lasers (QCLs) operating in single-mode at different wavelengths between 9.2 and 9.8 mu m. In each device, the output of a distributed feedback QCL is injected into a tapered QCL section which acts as an amplifier while maintaining a high beam quality due to adiabatic mode spreading. All array elements feature longitudinal as well as transverse single-mode emission at peak powers between 0.8 and 3.9W at room temperature. The high output power and excellent beam quality render the array highly suitable for stand-off spectroscopy applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4773377]