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arXiv · 1608.05250

Gain spectroscopy of a type-II VECSEL chip

Christian Lammers·Markus Stein·Christian Berger·Christoph Möller·Christian Fuchs·Antje Ruiz Perez·Arash Rahimi-Iman·Jörg Hader·Jerome Moloney·Wolfgang Stolz·Stephan W. Koch·Martin Koch
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Abstract

Using optical pump-white light probe spectroscopy the gain dynamics is investigated for a VECSEL chip which is based on a type-II heterostructure. The active region 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 experimental spectra. The results show a gain buildup on the type-II chip which is delayed relative to that of a type-I chip. This slower gain dynamics is attributed to a diminished cooling rate arising from reduced electron-hole scattering.

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Christian Lammers, Markus Stein, Christian Berger, Christoph Möller, Christian Fuchs, Antje Ruiz Perez, Arash Rahimi-Iman, Jörg Hader, Jerome Moloney, Wolfgang Stolz, Stephan W. Koch, Martin Koch. 2016-08-18. Gain spectroscopy of a type-II VECSEL chip. https://doi.org/10.1063/1.4971333

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