Séminaire

Mardi 13 Septembre 2022 à 11h00.

Random Lasers, Complex Systems, and the Nobel Prize in Physics 2021

''Random Lasers (RLs) and Random Fiber Lasers (RFLs) have been the subject of intense research since their first experimental demonstration in 1994 and 2007, respectively. These low coherence light sources rely on multiple scattering of light to provide optical feedback in a medium combining a properly excited gain material and a scattering disordered structure. The feedback by scattering makes it an open, complex system, different from a conventional laser. In this talk, I shall introduce the development of RLs and RFLs since their demonstration in 1994 and 2007, respectively, based on a review article recently published (Gomes, Moura, de Araújo, Raposo, Progress in Quantum Electronics 78 (2021) 100343). Then, in the second part of the talk, I will provide a series of examples of RLs and RFLs applications in different areas. This includes the use of RLs and RFLs as optical platforms for studies of complex systems, including photonics spin glass, turbulence, Lévy-like statistical behavior, among others. In the third and final part before concluding, I shall make the link between some of our work in photonics with the work with led to the Nobel Prize in Physics in 2021 by Giorgio Parisi in magnetism. Very interesting to our research, according to the document “Scientific Background on the Nobel Prize in Physics 2021” (https://www.nobelprize.org/uploads/2021/10/sciback_fy_en_21.pdf), one of our papers, cited in the document (page 11) along with other two publications, relates the work of two of the Nobelists: “Finally, the nature of the random laser system allows for the concomitant observation of replica symmetry breaking and connection between spin-glasses and turbulence [Gonzalez, I.R.R., Raposo, E.P., Macedo, A.M.S. GOMES, A.S.L et al. Coexistence of turbulence-like and glassy behaviours in a photonic system. Sci. Rep. 8, 17046, 2018], particularly nonlinear wave interactions, which link the early work of Hasselmann [….] to that of Parisi and to the role of disorder and fluctuations in complex systems in general”. We shall conclude with an outlook in the field of RLs and RFLs.''