Control of many electron states in semiconductor quantum dots by non-Abelian vector potentials

TL;DR

This paper explores how non-Abelian vector potentials, arising from adiabatic evolution of degenerate states in semiconductor quantum dots with spin-orbit coupling, enable control over many-electron states, unaffected by wavefunction antisymmetry.

Contribution

It derives equations linking many-electron non-Abelian vector potentials to single-electron potentials, revealing new control mechanisms in quantum dot systems.

Findings

Double degeneracy leads to non-Abelian vector potentials in quantum dots.

Wavefunction antisymmetry does not affect the matrix Berry phase.

Equations connect many-electron and single-electron non-Abelian potentials.

Abstract

Adiabatic time evolution of degenerate eigenstates of a quantum system provides a means for controlling electronic states since mixing between degenerate levels generates a matrix Berry phase. In the presence of spin-orbit coupling in n-type semiconductor quantum dots the electron Hamiltonian is invariant under time reversal operation and the many body groundstate may be doubly degenerate. This double degeneracy can generate non-Abelian vector potentials when odd number of electrons are present. We find that the antisymmetry of many electron wavefunction has no effect on the matrix Berry phase. We have derived equations that allow one to investigate the effect of electron correlations by expressing the non-Abelian vector potentials for many electron system in terms of single electron non-Abelian vector potentials.