Quantum Lab

Quantum networks play a crucial role for distributed quantum information processing, enabling the establishment of entanglement and quantum communication among distant nodes. Fundamentally, networks with independent sources allow for new forms of nonlocality, beyond the paradigmatic Bell’s theorem. Here we implement the simplest of such networks — the bilocality scenario — in an urban network … Continua a leggere

Boson Sampling is a computational paradigm representing one of the most viable and pursued approaches to demonstrate the regime of quantum advantage. Recent results have demonstrated significant technological leaps in single-photon generation and detection, leading to progressively larger experimental instances of Boson Sampling experiments in different photonic systems. However, a crucial requirement for a fully-fledged … Continua a leggere

The violation of a Bell inequality is the paradigmatic example of device-independent quantum information: the nonclassicality of the data is certified without the knowledge of the functioning of devices. In practice, however, all Bell experiments rely on the precise understanding of the underlying physical mechanisms. Given that, it is natural to ask: Can one witness … Continua a leggere

The orbital angular momentum (OAM) of light has been at the center of several classical and quantum applications for imaging, information processing and communication. However, the complex structure inherent in OAM states makes their detection and classification nontrivial in many circumstances. Most of the current detection schemes are based on models of the OAM states … Continua a leggere

Bell’s theorem is typically understood as the proof that quantum theory is incompatible with local hidden variable models. More generally, the violation of a Bell inequality can be seen as witnessing the impossibility of explaining quantum correlations with classical notion of causality. The violation of a Bell inequality, however, does not exclude that some level … Continua a leggere

Quantum key distribution—exchanging a random secret key relying on a quantum mechanical resource—is the core feature of secure quantum networks. Entanglement-based protocols offer additional layers of security and scale favorably with quantum repeaters, but the stringent requirements set on the photon source have made their use situational so far. Semiconductor-based quantum emitters are a promising … Continua a leggere

Giovedì 25 marzo 2021 alle ore 19.00, nell’ambito della manifestazione INgegneria INcontra, Fabio Sciarrino ha tenuto il seminario “La seconda rivoluzione quantistica: dal computer alle comunicazioni”. Le tecnologie quantistiche promettono di migliorare la nostra società in diversi ambiti – quali la crittografia, la simulazione di reazioni chimiche, l’ingegneria dei materiali e le nanotecnologie. Stiamo assistendo ad … Continua a leggere

Today, 14th of April, a new initiative from quantum scientists around the world has been launched:  the “World quantum day”.  The first global celebration will take place in one year, on the 14th of April 2022. The aim of this recurrence is to raise interest in quantum science’s achievements and allow a general audience to … Continua a leggere

Quantum coherence marks a deviation from classical physics, and has been studied as a resource for metrology and quantum computation. Finding reliable and effective methods for assessing its presence is then highly desirable. Coherence witnesses rely on measuring observables whose outcomes can guarantee that a state is not diagonal in a known reference basis. Here, … Continua a leggere

The generation and control of quantum correlations in high-dimensional systems is a major challenge in the present landscape of quantum technologies. Achieving such non-classical high-dimensional resources will potentially unlock enhanced capabilities for quantum cryptography, communication and computation. We propose a protocol that is able to attain entangled states of d-dimensional systems through a quantum-walk-based  transfer … Continua a leggere