Proton irradiation tests of quantum cascade lasers

The paper reports the investigations we carried out concerning the proton irradiation effects on a distributed-feedback quantum cascade laser. The irradiations were performed using the 3 MV Tandetron™ accelerator, the device exposure being of 10 14 p/cm 2 , 10 15 p/cm 2 and 10 16 p/cm 2 . Prior and post each irradiation we run off-line tests by measuring the current-voltage characteristic, the emitted optical power, the wavelength shift and the laser beam quality. During these testes we modified the driving current up to 240 mA and set the case temperature of the device at 10°C, 20°C and 30°C. Following these tests we noticed a decrease of: the emitted optical power and a blue shift of laser central wavelength.