“…Here, we note that the determination of the actual In diffusion parameters for an InGaAsP surface is not accessible by the present growth technique (MOVPE), but would be possible in molecular beam epitaxy (MBE) due to the temperature-dependent size of the "halo" formed around the droplets, which is directly linked to the group-III metallic droplet diffusion length. [29,[38][39][40][41] In this respect, studies are found for In on InP, [40] In on In 0.53 Ga 0.47 As, [29] In on In 0.52 Al 0.48 As, [42] In on GaAs, [41] and Ga on GaAs, [38,39] and to the best of our knowledge, studies of the In diffusion on InGaAsP surfaces are not known. Finally, it is worth pointing out that even though the QDs are not directly formed from the initial droplets as was found for the "standard" DE mode (see, e.g., our previous work on InAs/InP QDs), [12] there is no evidence for the presence of a strained wetting layer, confirmed by the optical characterizations in this work.…”