Gain spectroscopy of a type-II VECSEL chip

Using optical pump –white light probespectroscopy, the gaindynamics is investigated for a vertical-external-cavity surface-emitting laser chip, which is based on a type-IIheterostructure. The active region of the chip consists of a GaAs/(GaIn)As/Ga(AsSb)/(GaIn)As/GaAs multiple quantum well. For this structure, a fully microscopic theory predicts a modal room temperature gain at a wavelength of 1170  nm, which is confirmed by the experimentalspectra. The results show a gain buildup on the type-II chip that is delayed relative to that of a type-I chip. This slower gaindynamics is attributed to a diminished cooling rate arising from the reduced electron –hole scattering.

Source: Applied Physics Letters - December 8, 2016 Category: Physics Authors: C. Lammers, M. Stein, C. Berger, C. M öller, C. Fuchs, A. Ruiz Perez, A. Rahimi-Iman, J. Hader, J. V. Moloney, W. Stolz, S. W. Koch and M. Koch Source Type: research