Detail Project and Funding

Abstract: The present project intends to investigate the possibility of using the spectral and temporal “shape” of single photons, the elementary particles of the electromagnetic field, to extend applications of the quantum properties of light to new technologies (as foreseen in the next European Flagship on this theme). In fact, although single photons have already proved to be excellent carriers of quantum information, ie capable of transmitting it accurately and fundamentally immune to any interception even over long distances, they still have capabilities mostly limited to a binary “alphabet” (based on so-called “qubits”) and low interaction with matter, which makes it difficult to process and store this information effectively. Through the manipulation of their spectral-temporal shape, we first propose to access a much broader “alphabet” of possible states on which to store quantum information, passing from qubits to so-called “qudit”, with enormously greater capacities. In addition, this possibility will allow to better couple them with atomic systems for the realization of memories and quantum repeaters. Both main research lines are therefore addressed to the verification of the possibility of writing quantum information in the shape (temporal or spectral) of single photons and to transmit, store, and finally decode it efficiently. This is an extremely innovative line of research compared to the main current trends in the field and promises to open new avenues for the applications of quantum technologies. The project is part of the thematic line 9 “Le frontiere della chimica e della fisica: contiguità con le applicazioni” and extends the activities of the European ERA-Net project CHIST-ERA “QSCALE – Quantum technologies for extending the range of quantum communications” and Premiale MIUR “Oltre i limiti classici di misura”.

INO’s Experiments/Theoretical Study correlated:
Quantum light state engineering

The Scientific Results:
1) Conditional Hybrid Nonclassicality
2) Experimental quantum tomography of a homodyne detector
3) Measurement-Induced Strong Kerr Nonlinearity for Weak Quantum States of Light
4) Quantum Light State Engineering and Entanglement Generation by Multimode Photon Addition
5) Entangling Macroscopic Light States by Delocalized Photon Addition
6) Experimental Certification of Nonclassicality via Phase-Space Inequalities