Enhanced mobility of ternary InGaAs quantum wells through digital alloying

High In content InGaAs quantum wells (In $\ensuremath{\ge}$ 75%) are potentially useful for topological quantum computing and spintronics applications. In high-mobility InGaAs quantum wells, alloy disorder scattering is a limiting factor. In this paper, we demonstrate that by growing the InGaAs quantum wells as a digital alloy, or a short period superlattice, we can reduce the alloy disorder scattering within the quantum well and increase the peak 2 K electron mobility to $545\phantom{\rule{0.16em}{0ex}}000 {\mathrm{cm}}²$/Vs, which is the highest reported mobility for high-In content InGaAs quantum wells to the best of the authors' knowledge. Our results demonstrate that the digital alloy approach can be used to increase the mobility of quantum wells in random alloy ternary materials.