Quantum technologies (QT) are going to affect our daily life in the near future and will be ubiquitous. Already nowadays, QT offer new exciting opportunities both at the applied and at the fundamental level. Particularly interesting (at least for a theoretical physicist like me) is the investigation of the possibilities offered by QT in the investigation of fundamental physics, from quantum thermodynamics to the physics of spacetime. This is why I strongly collaborate with experimental groups interested in these topics and I try to connect theoretical constructs with viable ways to obtained their empirical verification.
Talbot-Lau effect beyond the point-particle approximation
Near-field matter-wave interferometry is an elegant way to directly verify the superposition principle which is at the basis of quantum mechanics. However, in order to keep testing the boundaries of quantum mechanics we need to look for large superposition of increasingly larger quantum objects. This is challenging per se and requires to take into account several environmental effects and adapt the formalism to the growing size of the objects of interest.
In this work, we consider near-field interferometry based on the Talbot effect with a single optical grating for large spherical particles beyond the point-particle approximation. We account for the suppression of the coherent grating effect and, at the same time, the enhancement of the decoherence effects due to scattering and absorption of grating photons. This work is relevant for all experimental proposals which aim to probe the superposition principle of quantum mechanics for mesoscopic objects using near-field interferometry.
Prospects for near-field interferometric tests of Collapse Models
In this follow up to the previous work, we applied our generalized framework for investigating the possibilities and limitations of ground-based near-field interferometric experiments with large dielectric particles for tests of collapse models of quantum mechanics. We show which are the opportunities ahead for these technological platforms and discuss several experimental challenges that need to be tackled.
Testing the foundation of quantum physics in space via Interferometric and non-interferometric experiments with mesoscopic nanoparticles
In this perspective article, we investigate the potential of space-based near-field interferometric and non-interferometric experiments with large dielectric particles for tests of collapse models of quantum mechanics. We discuss the opportunities ahead for these technological platforms and the challenges that space presents.
In this work we delve into the possibilities offered by the state-of-the-art of nanoparticle physics projected in the space environment. Furthermore, we also offer an ab-initio estimate of the potential of space-based interferometry with some of the largest systems ever considered and show that there is room for tests of quantum mechanics at an unprecedented level of detail.
Test quantum mechanics in space — invest US$1 billion
Our comment article for the pages of Nature is a call for action for an international effort to bring macroscopic quantum systems and experiments to space and use them to explore the foundations of quantum mechanics.
Quantum Physics in Space — a review
In this (massive) review work, we explore the state-of-the-art of both quantum technologies employed in the space environment and of the fundamental science objectives that can be achieved in space.
An Optomechanical Platform for Quantum Hypothesis Testing for Collapse Models
In this work, we show how a combination of a quantum optomechanicanical platform and quantum statistical inference can be used to investigate fundamental modifications to quantum mechanics.
Employing quantum hypothesis testing we shown the advantages that quantum resources can offer in the discrimination of competing hypothesis about the fundamental structure of quantum mechanics. In particular, we focus on an optomechanical system composed of two cavities employed to perform quantum channel discrimination. We show that input squeezed optical noise, and feasible measurement schemes on the output cavity modes, allow to obtain an advantage with respect to any comparable classical schemes. We apply these results to the discrimination of models of spontaneous collapse of the wavefunction, highlighting the possibilities offered by this scheme for fundamental physics searches.
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