Abstract

Quantum entanglement between distant degrees of freedom is an important resource for quantum information technologies, and of interest for fundamental research on quantum theory. As a concept, entanglement became widely known from the Einstein-Podolsky-Rosen paradox. Realizations were, until now, mainly carried out with pairs of photons or elementary particles, and with spins in simple and isolated quantum systems like alkali atoms.

I will present a novel approach for the realization and study of entanglement in solid state. Entanglement is generated between spin-wave modes of electron ensembles in two distant semiconductors. The states are prepared via optical pulses that interact with the spin ensembles, combined with quantum-optical measurement techniques. This provides a new model system for studies of how entanglement is spontaneously lost in complex quantum systems.