Photons have been a flagship system for studying quantum mechanics, advancing quantum
information science, and developing quantum technologies. Quantum entanglement …

How can one prove that a given quantum state is entangled? In this paper we review
different methods that have been proposed for entanglement detection. We first explain the …

According to quantum mechanics, a physical system can be in any linear superposition of its
possible states. Although the validity of this principle is routinely validated for microscopic …

Quantum metrology is one of the most promising applications of quantum technologies. The
aim of this research field is the estimation of unknown parameters exploiting quantum …

Taking advantage of quantum mechanics for executing computational tasks faster than
classical computers or performing measurements with precision exceeding the classical …

We summarize important recent advances in quantum metrology, in connection to
experiments in cold gases, trapped cold atoms and photons. First we review simple …

Quantum communication brings radically new capabilities that are provably impossible to
attain in any classical network. Here, we take the first step from a physics experiment to a …

We report the creation of Greenberger-Horne-Zeilinger states with up to 14 qubits. By
investigating the coherence of up to 8 ions over time, we observe a decay proportional to the …

Full control of multiple degrees of freedom of multiple particles represents a fundamental
ability for quantum information processing. We experimentally demonstrate an 18-qubit …

Distributed quantum metrology can enhance the sensitivity for sensing spatially distributed
parameters beyond the classical limits. Here we demonstrate distributed quantum phase …