Quantum Lab

Quantum Darwinism offers an explanation for the emergence of classical objective features — those we are used to at macroscopic scales — from quantum properties at the microscopic level. The interaction of a quantum system with its surroundings redundantly proliferates information to many parts of the environment, turning it accessible and objective to different observers. … Continua a leggere

Mutually entangled multi-photon states are at the heart of all-optical quantum technologies. While impressive progresses have been reported in the generation of such quantum light states using free space apparatus, high-fidelity high-rate on-chip entanglement generation is crucial for future scalability. In this work, we use a bright quantum-dot based single-photon source to demonstrate the high … Continua a leggere

Engineering single-photon states endowed with Orbital Angular Momentum (OAM) is a powerful tool for quantum information photonic implementations. Indeed, thanks to its unbounded nature, OAM is suitable to encode qudits allowing a single carrier to transport a large amount of information. Nowadays, most of the experimental platforms use nonlinear crystals to generate single photons through … Continua a leggere

In a Bell experiment, it is natural to seek a causal account of correlations wherein only a common cause acts on the outcomes. For this causal structure, Bell inequality violations can be explained only if causal dependencies are modelled as intrinsically quantum. There also exists a vast landscape of causal structures beyond Bell that can … Continua a leggere

This year the Nobel prize goes to Alain Aspect, John Francis Clauser and Anton Zeilinger celebrating the power of quantum mechanics. They have been recognized as the pioneering scientists which realized the first “experiments with entangled photons, establishing the violation of Bell inequalities” and therefore have been awarded by the Royal Swedish Academy of Sciences. … Continua a leggere

Quantum teleportation is one of the most striking consequences of quantum mechanics and is defined as the transmission and reconstruction of an unknown quantum state over arbitrary distances. This concept was introduced for the first time in 1993 by Charles Bennett and coworkers, it has then been experimentally demonstrated by several groups under different conditions … Continua a leggere

A joint paper between Sapienza, International Institute of Physics and Perimeter Institute on the observation of genuine nonlocality in a triangle network has been published in PRX Quantum!  Quantum networks are the center of many of the recent advances in quantum science, not only leading to the discovery of new properties in the foundations of quantum theory but … Continua a leggere

A joint paper between IFN-CNR, CNRS and Sapienza on a new method for the quantification of n-photon indistinguishability has been published in PRX! We report on a universal method to measure the genuine indistinguishability of n-photons – a crucial parameter that determines the accuracy of optical quantum computing. Our approach relies on a low-depth cyclic … Continua a leggere

On arxiv today the preprint of the work developed in the context of the international collaboration Quantum Information Structure of Spacetime (QISS). Detecting gravity mediated entanglement can provide evidence that the gravitational field obeys quantum mechanics. We report the result of a simulation of the phenomenon using a photonic platform. The simulation tests the idea … Continua a leggere

Entanglement-based quantum key distribution can enable secure communication in trusted node-free networks and over long distances. Although implementations exist both in fiber and in free space, the latter approach is often considered challenging due to environmental factors. Here, we implement a quantum communication protocol during daytime for the first time using a quantum dot source. … Continua a leggere