Valley population of donor states in highly strained silicon

Abstract Strain is extensively used to controllably tailor the electronic properties of materials. In context indirect band-gap semiconductors such as silicon, strain lifts valley degeneracy six conduction band minima, and by extension states electrons bound phosphorus donors. Here, single atoms are embedded in an engineered thin layer silicon strained 0.8% their wave function imaged using spatially resolved spectroscopy. A prevalence out-of-plane valleys confirmed from real-space images, a combination theoretical modelling tools assess how this repopulation effect can yield isotropic exchange tunnel interactions xy -plane relevant for atomically precise donor qubit devices. Finally, residual presence in-plane evidenced Fourier analysis both experimental atomistic calculations highlight importance higher orbital excited obtain relationship between population strain. Controlling degree freedom epilayers provides new competitive asset development donor-based quantum technologies silicon.