Dynamic generation of Bell states in a double-quantum-dot array including electron-phonon interaction
L. D. Contreras-Pulido and F. Rojas

We demonstrate theoretical stationary and dynamical Bell states generation in a system constituted by two parallel double quantum dots with one mobile electron each (proposed as two charge qubits) driven by an external potential difference applied to the second of the double dots. For coherent dynamics, it is shown that each one of the four Bell states is obtained through a suitable non-entangled initial condition as well as through the control of the time dependent external electric field. We analyze dissipative effects on such states formation, due to the coupling with a thermal bath of phonons. Via a markovian master equation approach, which includes the electron-phonon interaction, we found that Bell states probabilities are preserved for very low temperature but are adversely affected as temperature increases. In addition, we include concurrence and charge distribution calculations in order to characterize the double dot array. This electrostatic mechanism could be of interest in quantum computation, information and communication schemes.

© 2008 The American Physical Society.