Gregor Weihs

TL;DR: This work demonstrates entanglement involving the spatial modes of the electromagnetic field carrying orbital angular momentum, which provides a practical route to entangled states that involves many orthogonal quantum states, rather than just two Multi-dimensional entangled states could be of considerable importance in the field of quantum information, enabling, for example, more efficient use of communication channels in quantum cryptography.

TL;DR: In this article, the orbital angular momentum of photons is exploited to achieve multi-dimensional entanglement in higher dimensions, i.e., the state of the electromagnetic field with phase singularities (doughnut modes).

TL;DR: In this article, a strong violation of Bell's inequality was observed in an Einstein-Podolsky-Rosen-type experiment with independent observers, where the necessary spacelike separation of the observations is achieved by sufficient physical distance between the measurement stations, by ultrafast and random setting of the analyzers, and by completely independent data registration.

TL;DR: A novel key distribution scheme is implemented using Wigner's inequality to test the security of the quantum channel, and a variant of the BB84 protocol is realized.

TL;DR: A phase transition from a classical thermal mixed state to a quantum-mechanical pure state of exciton polaritons is observed in a GaAs multiple quantum-well microcavity from the decrease of the second-order coherence function.