Electron wavepacket propagation and entanglement in a chain of coupled quantum dots

Seminar Quantum Dynamics on July 07th, 2004

Georgios M. Nikolopoulos
Universität Darmstadt

Electron wavepacket propagation and entanglement in a chain of coupled quantum dots

Quantum computing schemes where the qubits are represented by spin-states of single electrons confined in individual quantum dots, are of particular interest to current research, since they are considered to be the most promising candidates for making large quantum computers.
Motivated by the necessity of understanding the dynamics of electron wavepackets in the presence of disorder and dissipation and to investigate the conditions under which coherent transport can be achieved, we study the dynamics of few-electron transport in a linear array of tunnel-coupled quantum dots. The electrons are considered initially well localized at the ends of the chain and their spin-states are well defined.
We find that this system exhibits a rich variety of coherent phenomena, ranging from electron wavepacket propagation and interference to many-particle bonding and collision. Furthermore, we show that choosing judiciously the couplings between adjacent quantum dots, one may achieve non-dispersive propagation of the electron wavepacket. A possible scenario capable of producing controllable mesoscopically separated EPR correlated pairs of electrons is presented.