Quantum communication networks involving the preparation, sharing, and measurement of quantum states are ubiquitous in quantum information. Of particular relevance within this context is to understand under which conditions a given quantum resource can give rise to correlations incompatible with a classical explanation. Here we consider the so-called prepare-and-measure scenario, in which a quantum or … Continua a leggere

Self-testing is a method of quantum state and measurement estimation that does not rely on assumptions about the inner working of the used devices. Its experimental realization has been limited to sources producing single quantum states so far. In this work, we experimentally implement two significant building blocks of a quantum network involving two independent … Continua a leggere

The PHOQUSING (PHOtonic Quantum SamplING machine) project, coordinated by the Quantum Information Lab, just started on 1 September 2020.The project was awarded a grant of more than 3 million Euros under the Horizon 2020 programme of the European Commission. The project will allow to join the forces of leading European Groups involved in quantum information … Continua a leggere

Quantum metrology is one of the most relevant applications of quantum information theory to quantum technologies. Here, quantum probes are exploited to overcome classical bounds in the estimation of unknown parameters. In this context, phase estimation, where the unknown parameter is a phase shift between two modes of a quantum system, is a fundamental problem. … Continua a leggere

Multi-particle interference is a key resource for quantum information processing, as exemplified by Boson Sampling. Hence, given its fragile nature, an essential desideratum is a solid and reliable framework for its validation. However, while several protocols have been introduced to this end, the approach is still fragmented and fails to build a big picture for … Continua a leggere

The image of the cover for AVS quantum science Volume 2 issue 2, provides a representation of a basic tool for photonic quantum phase estimation: the Mach-Zehnder interferometer. Here interfering quantum states of light can be exploited to extract information on unknown relative phase shifts, enhancing the sensitivity achievable by classical resources.  The cover image … Continua a leggere

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 resources, whose application can lead to enhanced performances with respect to classical strategies. Several physical quantum systems can be employed to develop quantum sensors, and photonic systems represent ideal … Continua a leggere

The intrinsic random nature of quantum physics offers novel tools for the generation of random numbers, a central challenge for a plethora of fields. Bell non-local correlations obtained by measurements on entangled states allow for the generation of bit strings whose randomness is guaranteed in a device-independent manner, i.e. without assumptions on the measurement and … Continua a leggere