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All SiGe alloys in the cubic crystal phase have an indirect bandgap. Therefore, SiGe alloys are typically considered as unusable as a light source. However, if the Si1-xGex atoms are arranged in a hexagonal crystal structure, the bandgap becomes direct for x>65%. The emission occurs with a nanosecond lifetime, and is tuneable from 1.8 to 3.4um by varying the SiGe composition. The hex-SiGe alloys have a relatively large separation between the direct and indirect conduction band minima, which makes it stand out as a Group IV light source [1]. The hex-SiGe alloys are realized as shells in a core-shell nanowire geometry, using wurtzite GaAs cores as epitaxial templates to copy the hexagonal stacking to the SiGe shells. Recently, photoluminescence studies of these core-shell nanowires resulted in the observation of amplified spontaneous emission (ASE) from hex-Si0.2Ge0.8, highlighting a positive material gain in this material system. The positive material gain is enabled by the direct bandgap of hex- Si0.2Ge0.8. Moreover, we have grown nanowires with multiple shells of different Si1-xGex compositions. Thus, these shells contain heterostructures of hex-Si1-xGex, having a type-I band alignment, allowing us to create hex-Ge/Si0.2Ge0.8 quantum wells with light emission up to room temperature. The observation of ASE, in combination with the ability to create type I QWs from hex-Si1-xGex, pave the way towards a laser based on hex-Si1-xGex alloys.