Strong electron-electron interactions in Si/SiGe quantum dots

Abstract

The authors implement a nonperturbative method for calculating the effects of strong electron-electron interactions, nearly degenerate electronic valleys, and interface disorder in multielectron silicon quantum dots. They show that all three ingredients play an important role in qubit experiments, and that Wigner-molecule physics in silicon can be substantially different from that in materials without valley degeneracy. The results provide key insights for the design and implementation of quantum dot qubits in silicon.