Localization and entanglement of two interacting electrons in a quantum-dot molecule

The localization of two interacting electrons in a coupled-quantum-dots sem i-conductor structure is demonstrated through numerical calculations of the time evolution of the two-electron wave function including the Coulomb int eraction between the electrons. The transition from the ground state to a l ocalized state is induced by an external, time-dependent, uniform electric field. It is found that while an appropriate constant field can localize bo th electrons in one of the wells, oscillatory fields can induce roughly equ al probabilities for both electrons to be localized in either well, generat ing an interesting type of localized and entangled state. We also show that shifting the field suddenly to an appropriate constant value can maintain in time both types localization.