Closed-shell formation in few-electron Si quantum dots

Multielectron quantum dots in Si have desirable properties as qubit platforms. For example, it has been shown that single-electron spins sitting above a closed shell of electrons can be electrically driven more effectively [1]. On the other hand, closed shells are also expected to be sensitive to the strength of electron-electron (e-e) interactions. Moreover, in Si quantum dots, the valley degree of freedom and disorder-induced valley-orbit coupling play critical roles in shell spectroscopy and qubit operations. In this talk, we theoretically investigate these effects by combining tight-binding calculations (to incorporate valley physics) and full-configuration interactions (to incorporate e-e interactions), with the goal of achieving a quantitative understanding of the underlying physics and rationally designing and manipulating qubits.

[1] Leon, R.C. et al. (2020).