Abstract

Coherent control of single atoms and generation of non-classical states has attracted widespread attention because of applications in quantum information science. Solid state systems are oftne considered to be promising and also difficult because of inhomogeneities and fast dephasing. Spin in solids, for example associated with quantum dots or single dopant atoms offer promising figures of merit for both parameters. As a particular example, the Nitrogen-Vacancy (NV) defect in ultrapure diamond shows long spin phase memory time (0.35 ms) evan at ambient conditions due to spin-free and rigid lattice. In addition to its excellent spin properties, spin selectivity of optical transitions of the NV defect allows initialization and readout of spin state with sensitivity routinely reaching single atom. The narrow spin resonance transitions of single defects make them a sensitive magnetometer at the nanoscale. I will discuss recent experiments aiming to use single NV defect for reading out spin states of proximal 13C and 14N nuclei. Magnetic coupling between electron spin of NV defects and neighboring electron or nuclear spin was used as a resource for generating entanglement between electron and nuclear spins.