Low-threshold operation of GaAs-based (GaIn)As/Ga(AsSb)/(GaIn)As W-quantum well lasers emitting in the O-band

Christian Fuchs; Imad Limame; Stefan Reinhard; Jannik Lehr; Jörg Hader; Jerome V. Moloney; Ada Bäumner; Stephan W. Koch; Wolfgang Stolz

arXiv · 2012.10996

Low-threshold operation of GaAs-based (GaIn)As/Ga(AsSb)/(GaIn)As W-quantum well lasers emitting in the O-band

Christian Fuchs·Imad Limame·Stefan Reinhard·Jannik Lehr·Jörg Hader·Jerome V. Moloney·Ada Bäumner·Stephan W. Koch·Wolfgang Stolz

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Abstract

The influence of the growth conditions as well as the device design on the device performance of (GaIn)As/Ga(AsSb)/(GaIn)As "W"-quantum well lasers is investigated. To this purpose, the epitaxy process is scaled to full two inch substrates for improved homogeneity while the growth process is carried out in a single run for an improved quality. Furthermore, the optical confinement factor is increased by increasing the aluminum concentration within the cladding layers to a value of 65%. The procedure is carried out for devices with emission wavelengths of 1.26 micrometer as well as 1.30 micrometer. Differential efficiencies as high as 58% and threshold current densities as low as 0.16 kA/cm^2 are observed in case of devices emitting at 1.26 micrometer at room temperature. Furthermore, excellent characteristic temperatures of T_0=(72 plus minus 5)K and T_1=(293 plus minus 16) K are recorded in the temperature range between 10 degree Celsius and 100 degree Celsius. Devices emitting at 1.30 micrometer exhibit differential efficiencies of 31% and threshold current densities of 0.50 kA/cm^2 at room temperature. Further improvements of these properties and wavelength extension schemes are briefly discssused.

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Christian Fuchs, Imad Limame, Stefan Reinhard, Jannik Lehr, Jörg Hader, Jerome V. Moloney, Ada Bäumner, Stephan W. Koch, Wolfgang Stolz. 2020-12-20. Low-threshold operation of GaAs-based (GaIn)As/Ga(AsSb)/(GaIn)As W-quantum well lasers emitting in the O-band. https://arxiv.org/abs/2012.10996

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