Quantum Dynamics of Electron-Nuclei Coupled System in Quantum Dots

We have investigated the dynamics of the electron-nuclei coupled system in quantum dots. The bunching of results of the electron spin measurements and the revival in the conditional probabilities are salient features of the nuclear spin memory. The underlying mechanism is the squeezing of the nuclear spin state and the correlations between the successive electron spin measurements. Further we make a proposal for the preparation and detection of superposition states of nuclear spins merely relying on electron spin measurements. For unpolarized, completely random nuclear spin state one can still trace the quantum interference effects. We discuss the realization of these schemes for electron spins on both single and double QDs.