FEW-PARTICLE STATES IN COUPLED ELECTRON-HOLE QUANTUM DOTS

We apply the exact diagonalization technique to calculate the ground and excited states of a bipolar artificial molecule composed of two vertically coupled quantum dots containing different types of carriers – electrons and holes – in equilibrium. In this system, the magnetic field tunes the relative role of intra-dot Coulomb interaction while the inter-dot separation sets the strength of inter-dot correlations. We find an intricate pattern of the switching of the ground-state angular momentum with increasing magnetic field and a rearrangement of approximate single-particle levels as a function of the inter-dot coupling strength.