Neutrino oscillations were discovered in 1998, providing the first evidence for massive neutrinos. A breakthrough in 2012 with the discovery of 𝝑13 opened up a new field of research to study quantum superposition effects over macroscopic distances (>100 km). In this seminar, this discovery will be presented and a new generation of experiments that study neutrino oscillations at large distances will be introduced.
These experiments -T2K, NoVA, JUNO, DUNE, and HyperKamiokande- have an ambitious goal: to fully determine the neutrino mass hierarchy and mixing parameters, which correspond to the lepton Yukawa sector of the Standard Model of Particle Physics. Results from ongoing experiments and expectations for the coming decade will be discussed.

Quantum Mechanics (QM), one of the most counter-intuitive and vanguard  descriptions of fundamental phenomena ever conceived, is not only at the heart of our understanding of the Universe, of matter, and of its interactions, but has also gained a primary role in science and technology with a large range of applications to our everyday life going from computing, to information theory, to safe communications. While we currently have no motivation to think that QM would stop to describe phenomena at short distances, at least below the Planck scale, it is interesting to ponder to what extent fundamental quantum effects can be probed beyond the atomic scales (10−10 m). Such a question has recently gained further momentum after the observation of entanglement in the spin of top/anti-top quark pairs at the LHC, the highest energy accelerator experiment on earth, operating at the TeV (10−19 m, 10−28 s) scale. This seminar will review the main ideas and results of applying quantum information concepts and methods to the study of fundamental interactions and illustrate the perspectives.

In this seminar, how coherent electromagnetic radiation at Tera-Hertz and mid-infrared frequencies can be used to drive complex solids, in an attempt to enhance their coherence, is discussed.
As collective excitations are driven nonlinearly, leading to coupling amongst otherwise virtually non-interacting normal modes of the material. Driving gives rise to non-thermal states with unconventional properties, and sometimes with emergent order. Interesting examples involve the nonlinear control of the crystal lattice, used to induce magnetic order, ferroelectricity and non-equilibrium superconductivity at high temperatures.

In this talk I will overview an ongoing project which revolves around the problem of defining QFTs on a non-Hausdorff spacetime. After a brief review of the locally-covariant formalism for QFT on curved spacetimes, we will spend some time understanding the “adjunction formalism” of non-Hausdorff differential geometry. In particular, we will see that ordinary globally-hyperbolic spacetimes can be “glued together” in order to describe non-Hausdorff spacetimes that exhibit topology change. Interestingly, this is in stark contrast to the usual version of topology change: in the non-Hausdorff case, our spacetime will be covered by a preferred set of globally-hyperbolic (Hausdorff) submanifolds, which doesn’t happen in the Hausdorff case. Once this observation is understood, we will see that the formalism of non-Hausdorff geometry seems to naturally cohere with locally covariant QFT: the QFTs on a non-Hausdorff spacetime can be described by “gluing together” QFTs defined on maximal globally-hyperbolic Hausdorff submanifolds. Time permitting, we will finish with an example of the Klein-Gordon field on a non-Hausdorff background, as well as some interesting observations for the near-future.

The development of fast and efficient quantum batteries is crucial for the prospects of quantum technologies. We show that both requirements are accomplished in the paradigmatic model of a harmonic oscillator strongly coupled to a highly non-Markovian thermal reservoir. At short times, a dynamical blockade of the reservoir prevents the leakage of energy towards its degrees of freedom, promoting a significant accumulation of energy in the battery with high efficiency. The evolution of the energy stored in the battery is almost periodic, which allows to avoid a too precise fine-tuning of the time at which the battery need to be disconnected from the charger. Moreover, our protocol is very efficient, allowing in principle to extract through unitary operations practically all the energy stored in the quantum battery, with a ratio between the energy that can be extracted and the work done by the charger which approaches the ideal unit limit. Our protocol may be envisioned with a quantum LC circuit playing the role of the battery and with the required environment being suitably engineered via state–of–the–art quantum circuits.

Future quantum information technologies have already found in integrated photonic platforms an excellent candidate in terms of robustness, scalability, complexity and overall integrability. At the Nanoscience Laboratory of the University of Trento, we design and experimentally study circuits for photons on a chip to harness the power of entanglement and interference for diverse quantum information processing tasks. In this talk, I will discuss a few research results to which I contributed over the past five years. First, I will introduce single-photon entanglement [1] and present how it can be exploited to generate quantum-certified random numbers using on-chip path-entangled single photons from an LED [2]. Second, I will show how qudits encoded in the path of single photons from an attenuated laser can be successfully employed to implement the first, to the best of our knowledge, photonic swap test circuit [3], an algorithm returning the inner product of two quantum states. Third, I will present some results related to our efforts toward the realization of a room-temperature quantum photonic integrated platform at visible-to-near infrared wavelengths [4]. Finally, I will conclude with some perspectives about our ongoing works and interests.

References

[1] S. Azzini, et al., Single-Particle Entanglement, Adv. Quantum Technol., 3: 2000014 (2020).

[2] N. Leone, et al., Generation of quantum-certified random numbers using on-chip path-entangled single photons from an LED, Photon. Res. 11, 1484-1499 (2023).

[3] A. Baldazzi, et al., A linear swap test circuit for quantum kernel estimation, arXiv preprint arXiv:2402.17923 (2024).

[4] M. Sanna, et al., SiN integrated photonic components in the visible to near-infrared spectral region, Opt. Express 32, 9081-9094 (2024).

Presentation of the six Curricula of the Master Degree in Physical Sciences.