2 Qubits: Coupled pair of DQD

Physical system and effective Hamiltonian Electrostatic coupling between DQD1 and DQD2

Computational basis and operators Operators:, Basis: New Basis:

with Definitive computational basis

General Hamiltonian With

Ground State Resonances CROT

First Excited State Levels are resonant at values given by and lines.

Quantum Logic Operations CROT First order process = a single electron tunnels

Quantum Logic Operations SWAP, FLIP 2nd. Order= simultaneous tunneling

Experimental steps Initialization at if are controled by gates voltages. coherent evolution time. Independent measurement of each DQD sub-systems

Results: coherent oscilations Damped oscilations between |LR> and |RR> (Fig.a) and |LL> and |RL> (Fig.b). Initialization |LR> at |LL> at CROT operations

Results: coherent oscilations Damped oscilations between |LR> and |RR> (Fig.a) and |LL> and |RL> (Fig.b). Initialization |LR> at |LL> at CROT operations t p =0.25ns

Results: coherent oscilations CROT operations t p =0.25ns

Results: Second order process Next slide

Results: Second order process First order process Numerical Simulations

How to prove there is a correlated dynamics?