UC Berkeley

The tunable physical and electronic structure of III-V semiconductor alloys renders them uniquely useful for a variety of applications, including biological imaging, transistors, and solar energy conversion. However, their fabrication typically requires complex gas phase instrumentation or growth from high-temperature melts, which consequently limits their prospects for widespread implementation. Furthermore, the need for lattice matched growth substrates in many cases confines the composition of the materials to a narrow range that can be epitaxially grown. In this work, we present a solution phase synthesis for indium gallium phosphide (In(x)Ga(1-x)P) alloy nanowires, whose indium/gallium ratio, and consequently, physical and electronic structure, can be tuned across the entire x = 0 to x = 1 composition range. We demonstrate the evolution of structural and optical properties of the nanowires, notably the direct to indirect band gap transition, as the composition is varied from InP to GaP. Our scalable, low-temperature synthesis affords compositional, structural, and electronic tunability and can provide a route for realization of broader In(x)Ga(1-x)P applications.