Coherent charge oscillation in a semiconductor double quantum dot.

The time evolution of a pulse-excited charge qubit in a semiconductor double quantum dot is investigated. All-electrical initialization and coherent gate control of the system are achieved, and coherent charge oscillation is observed through the transport measurements. The oscillation frequency and decoherence time T2 are estimated by fitting the transport data with a simple model. Possible decoherence mechanisms in a charge qubit system are pointed out and discussed in detail. [ABSTRACT FROM PUBLISHER]