Shi, Zhan and Simmons, C. B. and Ward, Daniel R. and Prance, Jonathan and Wu, Xian and Koh, Teck Seng and Gamble, John King and Savage, D. E. and Lagally, M. G. and Friesen, Mark and Coppersmith, S. N. and Eriksson, M. A. (2014) Fast coherent manipulation of three-electron states in a double quantum dot. Nature Communications, 5. ISSN 2041-1723
Full text not available from this repository.Abstract
An important goal in the manipulation of quantum systems is the achievement of many coherent oscillations within the characteristic dephasing time T2*. Most manipulations of electron spins in quantum dots have focused on the construction and control of two-state quantum systems, or qubits, in which each quantum dot is occupied by a single electron. Here we perform quantum manipulations on a system with three electrons per double quantum dot. We demonstrate that tailored pulse sequences can be used to induce coherent rotations between three-electron quantum states. Certain pulse sequences yield coherent oscillations fast enough that more than 100 oscillations are visible within a T2* time. The minimum oscillation frequency we observe is faster than 5 GHz. The presence of the third electron enables very fast rotations to all possible states, in contrast to the case when only two electrons are used, in which some rotations are slow.