Measurement of gain and losses of a midinfrared quantum cascade laser by wavelength chirping spectroscopy

作者：Benveniste E^*; Laurent S; Vasanelli A; Manquest C; Sirtori C; Teulon F; Carras M; Marcadet X

来源：Applied Physics Letters, 2009, 94(8): 081110.

DOI：10.1063/1.3089570

• distributed feedback lasers
• laser beams
• quantum cascade lasers
• semiconductor lasers
• spectroscopy

We present an optimized technique for the measurement of gain and losses of semiconductor lasers. We optically inject the beam of a distributed feedback laser (DFB) inside the cavity of the lasers under study. The DFB laser operates in a pulsed mode and shifts its emission wavelength as a function of time. This frequency chirp creates the Fabry-Perot fringes of the transmitted intensity that contains all the information on the cavity losses. The setup has been validated by a quantitative study of the losses as a function of the injected current, for a quantum cascade laser emitting at 7.6 mu m.

• 出版日期2009-2-23