NEW COMPLEXLIGHT WEBSITE
Our new, technologically advanced, website is online !
check for our recent posts!
Last Updated (Sunday, 30 October 2016 10:30)
This is the website of the Laboratory of Nonlinear Photonics and Theoretical Physics at the Department of Physics of the University Sapienza and the Institute for Complex Systems of the National Research Council. Our program is applying paradigms from the science of complex systems to light propagation, and investigating the development of complexity and self-organization in nonlinear waves. We want to test and deepen ideas of fundamental physics by using optics and photonics, and developing experiments, high performance computing approaches, and theory.
Solitons evaporate as black holes!
The fact that black holes are solitons is not very well known. Abdus Salam and others outlined this issue several years ago. Stephen Hawking predicted that Black Holes evaporate, and this is a quantum effect on classical gravity governed by the highly nonlinear Einstein-Hilbert equations.
Leone Villari, Ewan Wright, Fabio Biancalana and Claudio Conti report on the possibility that all types of classical solitons may evaporate in the quantum regime. A paper in the arXiv contains the theory on the exact quantization of the nonlinear Schroedinger equation: solitons emit a blackbody radiation spectrum at a temperature given by the same formula of Hawking!
This result is intriguing. On one hand, because it represents the first theoretical prediction of the Hawking radiation in a fully nonlinear quantum field theory. The standard Hawking theory relies on the quantization of a linear field in a curved background. The theory may hence provide insights for a true quantum gravity based on the complete quantization of the Einstein-Hilbert equations.
On the other hand, the result is also important because the Hawking radiation from a quantum soliton may furnish a novel highly tunable quantum source with many possible applications.
Last Updated (Saturday, 20 August 2016 07:27)
The Math of Irreversibility
In a paper in arXiv Giulia Marcucci and Claudio Conti report on the mathematical structures of the so-called Time Asymmetric Quantum Mechanics. This theory predicts that time-travel is not possible and explain evidences as the Big Bang or the decay of unstable particles. The authors argue that possible shaping of the initial state of a system may furnish a road to validate these fascinating developments in quantum mechanics. The work also follows the experimental evidence of the quantization of the decays rates.
The picture below shows a pictorial representation of the Gelfand triplet, the phase space of the Time Asymmetric Quantum Mechanics
Last Updated (Thursday, 28 July 2016 08:53)
Quantum X waves with orbital angular momentum
Multi-level quantum protocols may potentially supersede standard quantum optical polarization-encoded protocols in terms of amount of information transmission and security. However, for free space telecomunications, we do not have tools for limiting loss due to diffraction and perturbations, as for example turbulence in air.
In a recent manuscript in arXiv, Marco Ornigotti, Leone di Mauro Villari, Alexander Szeimeit, and Claudio Conti study propagation invariant quantum X-waves with angular momentum. The adopted representation expresses the electromagnetic field as a quantum gas of weakly interacting bosons. The resulting spatio-temporal quantized light pulses are not subject to diffraction and dispersion, and are intrinsically resilient to disturbances in propagation. Spontaneous down-conversion generates squeezed X-waves useful for quantum protocols. Surprisingly the orbital angural momentum affects the squeezing angle, and a characteristic axicon aperture for maximal squeezing exists.
There results may boost the applications in free space of quantum optical transmission and multi-level quantum protocols, and may also be relevant for novel kinds of interferometers, as satellite-based gravitational wave detectors.
Last Updated (Saturday, 16 July 2016 10:38)