Optically induced spin gates in coupled quantum dots using the electron-hole exchange interaction

We propose a fast optically induced two-qubit C-PHASE gate between two resident spins in a pair of coupled quantum dots. An excited bound state which extends over the two dots provides an effective electron-electron exchange interaction. The gate is made possible by the electron-hole exchange interaction, which isolates a single transition in the system. When combined with appropriate single-qubit rotations, this gate generates an entangled state of the two spins.