A5036401584- Quantum Information and Cryptography
- Quantum Mechanics and Applications
- Neural Networks and Reservoir Computing
- Quantum Computing Algorithms and Architecture
- Quantum optics and atomic interactions
- Photonic and Optical Devices
- Orbital Angular Momentum in Optics
- Optical Network Technologies
- Advanced Thermodynamics and Statistical Mechanics
- Near-Field Optical Microscopy
- Physical Unclonable Functions (PUFs) and Hardware Security
- Semiconductor Quantum Structures and Devices
- Philosophy and History of Science
- Mechanical and Optical Resonators
- Photonic Crystals and Applications
- Spectroscopy and Quantum Chemical Studies
- Cold Atom Physics and Bose-Einstein Condensates
- Biofield Effects and Biophysics
- Advanced Fluorescence Microscopy Techniques
- Laser-Matter Interactions and Applications
- Advanced Fiber Laser Technologies
- Semiconductor Lasers and Optical Devices
- Molecular spectroscopy and chirality
- Statistical Mechanics and Entropy
- Random lasers and scattering media
Sapienza University of Rome
2016-2025
Universidade Federal do Rio Grande do Norte
2017
University of Cologne
2017
University of Concepción
2013-2015
Quantum key distribution---exchanging a random secret relying on quantum mechanical resource---is the core feature of secure networks. Entanglement-based protocols offer additional layers security and scale favorably with repeaters, but stringent requirements set photon source have made their use situational so far. Semiconductor-based emitters are promising solution in this scenario, ensuring on-demand generation near-unity-fidelity entangled photons record-low multi-photon emission, latter...
Light beams having a vectorial field structure - or polarization that varies over the transverse profile and central optical singularity are called vector-vortex (VV) may exhibit specific properties, such as focusing into "light needles" rotation invariance, with applications ranging from microscopy light trapping to communication metrology. Individual photons in form of single-particle quantum entanglement between different degrees freedom. On other hand, states two can be also entangled...
Abstract Mutually entangled multi-photon states are at the heart of all-optical quantum technologies. While impressive progresses have been reported in generation such light using free space apparatus, high-fidelity high-rate on-chip entanglement is crucial for future scalability. In this work, we use a bright quantum-dot based single-photon source to demonstrate high fidelity 4-photon Greenberg-Horne-Zeilinger (GHZ) with low-loss reconfigurable glass photonic circuit. We reconstruct density...
Non-locality stands nowadays not only as one of the cornerstones quantum theory, but also plays a crucial role in information processing. Several experimental investigations nonlocality have been carried out over years. In spite their fundamental relevance, however, all previous experiments do consider ingredient that is ubiquitous networks: fact correlations between distant parties are mediated by several, typically independent, sources states. Here, using photonic setup we investigate...
Bell's theorem was a cornerstone for our understanding of quantum theory and the establishment Bell non-locality played crucial role in development information. Recently, its extension to complex networks has been attracting growing attention, but deep characterization behavior is still missing this novel context. In work we analyze correlations arising bilocality scenario, that tripartite network where between parties are mediated by two independent sources states. First, prove non-bilocal...
The number of parameters describing a quantum state is well known to grow exponentially with the particles. This scaling limits our ability characterize and simulate evolution arbitrary states systems, no more than few qubits. However, from computational learning theory perspective, it can be shown that approximately learned using measurements growing linearly Here, we experimentally demonstrate this linear in optical systems up 6 Our results highlight power investigate information, provide...
Abstract The launch of a satellite capable distributing entanglement through long distances and the first loophole-free violation Bell inequalities are milestones indicating clear path for establishment quantum networks. However, nonlocality in networks with independent sources has only been experimentally verified simple tripartite networks, via bilocality inequalities. Here, by using scalable photonic platform, we implement star-shaped consisting up to five distant nodes four sources. We...
Boson Sampling is a computational paradigm representing one of the most viable and pursued approaches to demonstrate regime quantum advantage. Recent results have demonstrated significant technological leaps in single-photon generation detection, leading progressively larger experimental instances experiments different photonic systems. However, crucial requirement for fully-fledged platform solving this problem capability implementing large-scale interferometers, that must simultaneously...
Abstract Quantum information processing is nowadays an established branch of quantum mechanics applications. Recent results in different areas, ranging from communications to computing, show that technologies are advancing towards being mature platforms with substantial advantages over traditional classical protocols. optics and photonic apparatuses one the best candidates for realization processors. In this context, integrated essential components miniaturisation such complex optical...
Any practical realization of entanglement-based quantum communication must be intrinsically secure and able to span long distances avoiding the need a straight line between communicating parties. The violation Bell's inequality offers method for certification links without knowing inner workings devices. Energy-time entanglement satisfies all these requirements. However, currently there is fundamental obstacle with standard configuration adopted: an intrinsic geometrical loophole that can...
Entanglement distribution between distant parties is one of the most important and challenging tasks in quantum communication. Distribution photonic entangled states using optical fiber links a fundamental building block towards networks. Among different degrees freedom, orbital angular momentum (OAM) promising due to its natural capability encode high dimensional states. In this article, we experimentally demonstrate hybrid polarization-vector vortex photon pairs. To end, exploit recently...
Abstract Entanglement-based quantum key distribution can enable secure communication in trusted node-free networks and over long distances. Although implementations exist both fiber free space, the latter approach is often considered challenging due to environmental factors. Here, we implement a protocol during daytime for first time using dot source. This technology presents advantages terms of narrower spectral bandwidth—beneficial filtering out sunlight—and negligible multiphoton emission...
Abstract Quantum walks represent paradigmatic quantum evolutions, enabling powerful applications in the context of topological physics and computation. They have been implemented diverse photonic architectures, but realization two-particle dynamics on a multidimensional lattice has hitherto limited to continuous-time evolutions. To fully exploit computational capabilities interference it is crucial develop platforms handling multiple photons that propagate across lattices. Here, we report...
Quantum superposition of high-dimensional states enables both computational speed-up and security in cryptographic protocols. However, the exponential complexity tomographic processes makes certification these properties a challenging task. In this work, we experimentally certify coherence witnesses tailored for quantum systems increasing dimension using pairwise overlap measurements enabled by six-mode universal photonic processor fabricated with femtosecond laser writing technology....
Engineering single-photon states endowed with orbital angular momentum (OAM) is a powerful tool for quantum information photonic implementations. Indeed, due to its unbounded nature, OAM suitable encoding qudits, allowing single carrier transport large amount of information. Most the experimental platforms employ spontaneous parametric down-conversion processes generate photons, even if this approach intrinsically probabilistic, leading scalability issues an increasing number qudits....
Nonclassical correlations arising in complex quantum networks are attracting growing interest, both from a fundamental perspective and for potential applications information processing. In particular, an entanglement swapping scenario new kind of arise, the so-called nonbilocal that incompatible with local realism augmented assumption sources states used experiment independent. practice, however, bilocality tests impose strict constraints on experimental setup particular to presence shared...
Bell's theorem is typically understood as the proof that quantum theory incompatible with local-hidden-variable models. More generally, we can see violation of a Bell inequality witnessing impossibility explaining correlations classical causal The inequality, however, does not exclude models where some level measurement dependence allowed, is, choice made by observers be correlated source generating systems to measured. Here, show quantitatively upper bounded if arrange test within network....
Abstract In a Bell experiment, it is natural to seek causal account of correlations wherein only common cause acts on the outcomes. For this structure, inequality violations can be explained if dependencies are modeled as intrinsically quantum. There also exists vast landscape structures beyond that witness nonclassicality, in some cases without even requiring free external inputs. Here, we undertake photonic experiment realizing one such example: triangle network, consisting three...
Using a quantum triangle network, in which each of the three parties can perform number separable and independent measurements, genuine tripartite nonlocality is achieved without employment source.
Since Bell's theorem, it is known that local realism fails to explain quantum phenomena. Bell inequality violations manifestly show the incompatibility of theory with classical notions cause and effect. As recently found, however, instrumental scenario-a pivotal tool in causal inference-allows for nonclassicality signatures going beyond this paradigm. If we are not limited observational data can intervene our setup, then witness bounds on influence among involved variables even when no...
Randomness certification is a foundational and practical aspect of quantum information science, essential for securing communication protocols. Traditionally, these protocols have been implemented validated with single entanglement source, as in the paradigmatic Bell scenario. However, advancing to support more complex configurations involving multiple sources key building robust architectures realizing large-scale networks. In this work, we show how certify randomness an...
Device-independent quantum communication will require a loophole-free violation of Bell inequalities. In typical scenarios where line sight between the communicating parties is not available, it convenient to use energy-time entangled photons due intrinsic robustness while propagating over optical fibers. Here we show an Clauser-Horne-Shimony-Holt inequality with two separated by 3.7 km deployed fiber network belonging University Concepción in Chile. Remarkably, this first spatially that...
Structured photons are nowadays an interesting resource in classical and quantum optics due to the richness of properties they show under propagation, focusing their interaction with matter. Vectorial modes light particular, a class where polarization varies across beam profile, have already been used several areas ranging from microscopy information. One key ingredients needed exploit full potential complex domain is control interference, crucial fields like communication, sensing...