@article{Getman2021,

title = {Broadband vectorial ultrathin optics with experimental efficiency up to 99% in the visible region via universal approximators},

author = {F Getman and M Makarenko and A Burguete-Lopez and A Fratalocchi},

url = {https://doi.org/10.1038/s41377-021-00489-7},

doi = {10.1038/s41377-021-00489-7},

issn = {2047-7538},

year  = {2021},

date = {2021-03-04},

journal = {Light: Science & Applications},

volume = {10},

number = {1},

pages = {47},

abstract = {Integrating conventional optics into compact nanostructured surfaces is the goal of flat optics. Despite the enormous progress in this technology, there are still critical challenges for real-world applications due to the limited operational efficiency in the visible region, on average lower than 60%, which originates from absorption losses in wavelength-thick (≈ 500thinspacenm) structures. Another issue is the realization of on-demand optical components for controlling vectorial light at visible frequencies simultaneously in both reflection and transmission and with a predetermined wavefront shape. In this work, we developed an inverse design approach that allows the realization of highly efficient (up to 99%) ultrathin (down to 50thinspacenm thick) optics for vectorial light control with broadband input--output responses in the visible and near-IR regions with a desired wavefront shape. The approach leverages suitably engineered semiconductor nanostructures, which behave as a neural network that can approximate a user-defined input--output function. Near-unity performance results from the ultrathin nature of these surfaces, which reduces absorption losses to near-negligible values. Experimentally, we discuss polarizing beam splitters, comparing their performance with the best results obtained from both direct and inverse design techniques, and new flat-optics components represented by dichroic mirrors and the basic unit of a flat-optics display that creates full colours by using only two subpixels, overcoming the limitations of conventional LCD/OLED technologies that require three subpixels for each composite colour. Our devices can be manufactured with a complementary metal-oxide-semiconductor (CMOS)-compatible process, making them scalable for mass production at low cost.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/adma.202108013c,

title = {Large-Scale and Wide-Gamut Coloration at the Diffraction Limit in Flexible, Self-Assembled Hierarchical Nanomaterials},

author = {Ning Li and Fei Xiang and Maxim S. Elizarov and Maxim Makarenko and Arturo B. Lopez and Fedor Getman and Marcella Bonifazi and Valerio Mazzone and Andrea Fratalocchi},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202108013},

doi = {https://doi.org/10.1002/adma.202108013},

year  = {2021},

date = {2021-01-01},

journal = {Advanced Materials},

pages = {2108013},

abstract = {Abstract Unveiling physical phenomena that generate controllable structural coloration is at the center of significant research efforts due to the platform potential for the next generation of printing, sensing, displays, wearable optoelectronics components, and smart fabrics. Colors based on e-beam facilities possess high resolutions above 100k dots per inch (DPI), but limit manufacturing scales up to 4.37 cm2, while requiring rigid substrates that are not flexible. State-of-art scalable techniques, on the contrary, provide either narrow gamuts or small resolutions. A common issue of current methods is also a heterogeneous resolution, which typically changes with the color printed. Here, a structural coloration platform with broad gamuts exceeding the red, green, and blue (RGB) spectrum in inexpensive, thermally resistant, flexible, and metallic-free structures at constant 101 600 DPI (at the diffraction limit), obtained via mass-production manufacturing is demonstrated. This platform exploits a previously unexplored physical mechanism, which leverages the interplay between strong scattering modes and optical resonances excited in fully 3D dielectric nanostructures with suitably engineered longitudinal profiles. The colors obtained with this technology are scalable to any area, demonstrated up to the single wafer (4 in.). These results open real-world applications of inexpensive, high-resolution, large-scale structural colors with broad chromatic spectra.},

keywords = {dielectrics, nanostructured materials, optical nanoresonators, structural color},

pubstate = {published},

tppubtype = {article}

}

@article{Makarenko2020,

title = {Generalized Maxwell projections for multi-mode network Photonics},

author = {M Makarenko and A Burguete-Lopez and F Getman and A Fratalocchi},

url = {https://doi.org/10.1038/s41598-020-65293-6},

doi = {10.1038/s41598-020-65293-6},

issn = {2045-2322},

year  = {2020},

date = {2020-06-03},

journal = {Scientific Reports},

volume = {10},

number = {1},

pages = {9038},

abstract = {The design of optical resonant systems for controlling light at the nanoscale is an exciting field of research in nanophotonics. While describing the dynamics of few resonances is a relatively well understood problem, controlling the behavior of systems with many overlapping states is considerably more difficult. In this work, we use the theory of generalized operators to formulate an exact form of spatio-temporal coupled mode theory, which retains the simplicity of traditional coupled mode theory developed for optical waveguides. We developed a fast computational method that extracts all the characteristics of optical resonators, including the full density of states, the modes quality factors, and the mode resonances and linewidths, by employing a single first principle simulation. This approach can facilitate the analytical and numerical study of complex dynamics arising from the interactions of many overlapping resonances, defined in ensembles of resonators of any geometrical shape and in materials with arbitrary responses.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{smirnov2018bistable,

title = {Bistable lasing in parity-time symmetric coupled fiber rings},

author = {Sergey V Smirnov and Maxim O Makarenko and Sergey V Suchkov and Dmitry Churkin and Andrey A Sukhorukov},

year  = {2018},

date = {2018-01-01},

journal = {Photonics Research},

volume = {6},

number = {4},

pages = {A18--A22},

publisher = {Optical Society of America},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/adma.202108013b,

title = {Large-Scale and Wide-Gamut Coloration at the Diffraction Limit in Flexible, Self-Assembled Hierarchical Nanomaterials},

author = {Ning Li and Fei Xiang and Maxim S. Elizarov and Maxim Makarenko and Arturo B. Lopez and Fedor Getman and Marcella Bonifazi and Valerio Mazzone and Andrea Fratalocchi},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202108013},

doi = {https://doi.org/10.1002/adma.202108013},

journal = {Advanced Materials},

volume = {n/a},

number = {n/a},

pages = {2108013},

abstract = {Abstract Unveiling physical phenomena that generate controllable structural coloration is at the center of significant research efforts due to the platform potential for the next generation of printing, sensing, displays, wearable optoelectronics components, and smart fabrics. Colors based on e-beam facilities possess high resolutions above 100k dots per inch (DPI), but limit manufacturing scales up to 4.37 cm2, while requiring rigid substrates that are not flexible. State-of-art scalable techniques, on the contrary, provide either narrow gamuts or small resolutions. A common issue of current methods is also a heterogeneous resolution, which typically changes with the color printed. Here, a structural coloration platform with broad gamuts exceeding the red, green, and blue (RGB) spectrum in inexpensive, thermally resistant, flexible, and metallic-free structures at constant 101 600 DPI (at the diffraction limit), obtained via mass-production manufacturing is demonstrated. This platform exploits a previously unexplored physical mechanism, which leverages the interplay between strong scattering modes and optical resonances excited in fully 3D dielectric nanostructures with suitably engineered longitudinal profiles. The colors obtained with this technology are scalable to any area, demonstrated up to the single wafer (4 in.). These results open real-world applications of inexpensive, high-resolution, large-scale structural colors with broad chromatic spectra.},

keywords = {dielectrics, nanostructured materials, optical nanoresonators, structural color},

pubstate = {published},

tppubtype = {article}

}