Electron spin dynamics and hyperfine interaction in coupled quantum dots

We have investigated the quantum dynamics of the electron-nuclei coupled system in a double quantum dot and discovered a couple of new phenomena related to the quantum nature of nuclear spin system. Especially, the bunching of results of the electron spin measurements and the revival in the conditional probabilities are salient features of quantum dynamics. The underlying mechanism is the squeezing of the nuclear spin state through the electron spin measurements. This squeezing is expected to lead to the elongation of the electron spin coherence time. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)