arXiv subjects

P. Piergentili

Publications and source records attributed to P. Piergentili.

3 recordsLinked to original sources

arXiv2026

Probing gravitational interaction between milligram optomechanical oscillators operating in the quantum regime

We present an ongoing optomechanical experiment aimed at detecting gravitational interaction between milligram-scale oscillators, and exploring its interplay with quantum mechanics. The setup employs two microfabricated oscillators coupled via gravity and read out through a high-finesse optical cavity, at ultra-cryogenic temperature. Finite element simulations, noise modelling, and sensitivity estimates demonstrate that gravitational coupling can be detected with integration times ranging from minutes to hours. The experiment establishes a realistic platform for probing gravitational effects in systems approaching the quantum regime.

quant-ph↗

arXiv2025

Correlated Quantum Airy Photons: An Analytical Approach

We describe the generation of correlated photon pairs by means of spontaneous parametric down-conversion of an optical pump in the form of a finite energy Airy beam. The optical system function, which contributes to the propagation of the down-converted beam before being registered by the detectors, is computed. The spectral function is utilized to calculate the biphoton amplitude for finding the coincidence count of the inbound Airy photons in both far-field and near-field configurations. We report the reconstruction of the finite energy Airy beam in the spatial correlation of the down-converted beams in near field scenario. In far field, the coincidence counts resembles the probability density of the biphoton in momentum space, revealing a direct mapping of the anti-correlation of the biphoton momentum. By examining the spatial Schmidt modes, we also demonstrate that longer crystals have tighter real-space correlations, but higher-dimensional angular correlations, whereas shorter crystals have fewer modes in momentum space and broader multimode correlations in position space.

quant-ph↗

arXiv2020

Probing quantum gravity effects with quantum mechanical oscillators

Phenomenological models aiming to join gravity and quantum mechanics often predict effects that are potentially measurable in refined low-energy experiments. For instance, modified commutation relations between position and momentum, that accounts for a minimal scale length, yield a dynamics that can be codified in additional Hamiltonian terms. When applied to the paradigmatic case of a mechanical oscillator, such terms, at the lowest order in the deformation parameter, introduce a weak intrinsic nonlinearity and, consequently, deviations from the classical trajectory. This point of view has stimulated several experimental proposals and realizations, leading to meaningful upper limits to the deformation parameter. All such experiments are based on classical mechanical oscillators, i.e., excited from a thermal state. We remark indeed that decoherence, that plays a major role in distinguishing the classical from the quantum behavior of (macroscopic) systems, is not usually included in phenomenological quantum gravity models. However, it would not be surprising if peculiar features that are predicted by considering the joined roles of gravity and quantum physics should manifest themselves just on purely quantum objects. On the base of this consideration, we propose experiments aiming to observe possible quantum gravity effects on macroscopic mechanical oscillators that are preliminary prepared in a high purity state, and we report on the status of their realization.

quant-ph↗