  External control over the electron and hole wavefunctions geometry and
topology is investigated in a p-i-n diode embedding a dot-in-a-well InAs/GaAsSb
quantum structure with type II band alignment. We find highly tunable exciton
dipole moments and largely decoupled exciton recombination and ionization
dynamics. We also predicted a bias regime where the hole wavefunction topology
changes continuously from quantum dot-like to quantum ring-like as a function
of the external bias. All these properties have great potential in advanced
electro-optical applications and in the investigation of fundamental spin-orbit
phenomena.
