A research team paved a way to achieve unexplored III-V semiconductor nanostructures. They grew branched GaAs nanowires with a nontoxic Bi element employing characteristic structural modifications correlated with metallic droplets, as well as crystalline defects and orientations. The finding provides a rational design concept for the creation of semiconductor nanostructures with the concentration of constituents beyond the fundamental limit, making it potentially applicable to novel efficient near-infrared devices and quantum electronics.