Evaluating the “quantumness” of a quantum compute

INL, Sapienza University of Rome, CNR-INF and Politecnico di Milano, have recently published a new study that demonstrates how to certify several quantum properties of devices of increasing complexity. The paper was published on November 3rd in the journal Science Advances (full publication here). Programmable optical circuits are one of the leading architectures for quantum information processing. They enable tests of key aspects … Leggi tutto

“Experimental certification of contextuality, coherence and dimension in a programmable universal photonic processor” published on Science Advances

Programmable integrated optical circuits are among the leading architectures for quantum information processing, enabling tests of foundational properties of quantum mechanics, with applications in metrology, cryptography, and computation. The nonclassical processing of information encoded by quantum states of light in these devices lies at the core of these applications. As new devices grow in size … Leggi tutto

Interferometric imaging of amplitude and phase of spatial biphoton states

High-dimensional biphoton states are promising resources for quantum applications, ranging from high-dimensional quantum communications to quantum imaging. A pivotal task is fully characterizing these states, which is generally time-consuming and not scalable when projective measurement approaches are adopted; however, new advances in coincidence imaging technologies allow for overcoming these limitations by parallelizing multiple measurements. Here … Leggi tutto

Deep reinforcement learning for quantum multiparameter estimation

Estimation of physical quantities is at the core of most scientific research, and the use of quantum devices promises to enhance its performances. In real scenarios, it is fundamental to consider that resources are limited, and Bayesian adaptive estimation represents a powerful approach to efficiently allocate, during the estimation process, all the available resources. However, … Leggi tutto

Interferometric imaging of amplitude and phase of spatial biphoton states

High-dimensional biphoton states are promising resources for quantum applications, ranging from high-dimensional quantum communications to quantum imaging. A pivotal task is fully characterising these states, which is generally time-consuming and not scalable when projective measurement approaches are adopted. However, new advances in coincidence imaging technologies allow for overcoming these limitations by parallelising multiple measurements. Here, … Leggi tutto

Experimental genuine tripartite nonlocality in a quantum triangle network has been published in PRX Quantum!

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 … Leggi tutto

Certification of Gaussian Boson Sampling via graph theory

Gaussian Boson Sampling is a non-universal model for quantum computing inspired by the original formulation of the Boson Sampling problem. Nowadays, it represents a paradigmatic quantum platform to reach the quantum advantage regime in a specific computational model. Indeed, thanks to the implementation in photonics-based processors, the latest Gaussian Boson Sampling experiments have reached a … Leggi tutto

Ab-initio experimental violation of Bell inequalities

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 … Leggi tutto