Resumen del trabajo presentado a la Conferencia Española de Nanofotónica (CEN), celebrada en Vigo del 20 al 22 de septiembre de 2021. ; The authors acknowledge the funding by: -Ministerio de Ciencia e Innovación project PID2019-107432GBI00P, FIS2017-87363-P, Eusko Jaurlaritza project KK-2019/00101, and Project IT1164-19 for consolidated groups of the Basque University, through the Department of Education, Research and Universities of the Basque Government. ; Peer reviewed
In this work, we experimentally show that quantum entanglement can be symmetry protected in the interaction with a single subwavelength plasmonic nanoaperture, with a total volume of V∼0.2λ3. In particular, we experimentally demonstrate that two-photon entanglement can be either completely preserved or completely lost after the interaction with the nanoaperture, solely depending on the relative phase between the quantum states. We achieve this effect by using specially engineered two-photon states to match the properties of the nanoaperture. In this way we can access a symmetry protected state, i.e., a state constrained by the geometry of the interaction to retain its entanglement. In spite of the small volume of interaction, we show that the symmetry protected entangled state retains its main properties. This connection between nanophotonics and quantum optics probes the fundamental limits of the phenomenon of quantum interference. ; L. M. and F. S. acknowledge financial support from the European Union Horizon 2020 program, within the European Research Council (ERC) Grant No. 694683, PHOSPhOR. G. M. T. acknowledges financial support from the Australian Research Council through the Future fellowship program FT110100924 and the Spanish Ministry of Science, Innovation and Universities (MICIN) Project No. FIS2017-87363-P. ; Peer reviewed
The polarization of the light scattered by an optically dense and random solution of dielectric nanoparticles shows peculiar properties when the scatterers exhibit strong electric and magnetic polarizabilities. While the distribution of the scattering intensity in these systems shows the typical irregular speckle patterns, the helicity of the incident light can be fully conserved when the electric and magnetic polarizabilities of the scatterers are equal. We show that the multiple scattering of helical beams by a random dispersion of "dual" dipolar nanospheres leads to a speckle pattern exhibiting a perfect isotropic constant polarization, a situation that could be useful in coherent control of light as well as in lasing in random media ; M. K. S. and J. A. acknowledge funding from Project No. FIS2013-41184-P of the Spanish Ministry of Economy and Competitiveness, the Project No. ETORTEK IE14-393 NANOGUNE'14 of the Department of Industry of the Government of the Basque Country, Project No. IT756-13 of the Department of Education and Culture of the Basque Country, and Grant No. AP-2012-4204 from the Spanish Ministry of Education, Culture, and Sport. J. J. S. acknowledges financial support by the Spanish MINECO (Grant No. FIS2012-36113) and by IKERBASQUE.G.M.-T. is supported by the Australian Research Council (Grant No. FT110100924)
Under the terms of the Creative Commons Attribution License 3.0 (CC-BY). ; The polarization of the light scattered by an optically dense and random solution of dielectric nanoparticles shows peculiar properties when the scatterers exhibit strong electric and magnetic polarizabilities. While the distribution of the scattering intensity in these systems shows the typical irregular speckle patterns, the helicity of the incident light can be fully conserved when the electric and magnetic polarizabilities of the scatterers are equal. We show that the multiple scattering of helical beams by a random dispersion of >dual> dipolar nanospheres leads to a speckle pattern exhibiting a perfect isotropic constant polarization, a situation that could be useful in coherent control of light as well as in lasing in random media. ; M. K. S. and J. A. acknowledge funding from Project No. FIS2013-41184-P of the Spanish Ministry of Economy and Competitiveness, the Project No. ETORTEK IE14-393 NANOGUNE'14 of the Department of Industry of the Government of the Basque Country, Project No. IT756-13 of the Department of Education and Culture of the Basque Country, and Grant No. AP-2012-4204 from the Spanish Ministry of Education, Culture, and Sport. J. J. S. acknowledges financial support by the Spanish MINECO (Grant No. FIS2012-36113) and by IKERBASQUE. G. M.-T. is supported by the Australian Research Council (Grant No. FT110100924). ; Peer Reviewed
Spin-orbit interaction of light can lead to the so-called optical mirages, i.e., a perceived displacement in the position of a particle due to the spiraling structure of the scattered light. In electric dipoles, the maximum displacement is subwavelength and does not depend on the optical properties of the scatterer. Here we will show that the optical mirage in high refractive index dielectric nanoparticles depends strongly on the ratio between electric and magnetic dipolar responses. When the dual symmetry is satisfied (at the first Kerker condition), there is a considerable enhancement (far above the wavelength) of the spin-orbit optical mirage which can be related to the emergence of an optical vortex in the backscattering direction. ; This research was supported by the Spanish Ministerio de Economía y Competitividad (MICINN) and European Regional Development Fund (ERDF) Projects No. FIS2014-55987-P, No. FIS2015-69295-C3-3-P, and No. FIS2017-82804-P, by the Basque Dep. de Educación Project No. PI-2016-1-0041 and by the Basque Government ELKARTEK program (KK-2016/00030, KK-2017/00089). A.G.-E. received funding from the Fellows Gipuzkoa fellowship of the Gipuzkoako Foru Aldundia through FEDER "Una Manera de hacer Europa."