2.0 micron DFB laser diodes (in the following a 2004 nm device is exemplary presented) show unique device performance to meet the requirements of our customers. High side mode suppression ratio (SMSR) and high spectral purity make them perfectly suited for applications like e.g. CO2 spectroscopy. Mode-hop free DFB emission with a high side mode suppression ratio (SMSR) around 35 dB is guaranteed for the device in the entire specified temperature and current range of operation.