Date:
Thursday, September 13, 2018, 12:00pm to 1:00pm
Location:
LISE 303
Nanostructured metasurface optics for Orbital Angular Momentum spectroscopy
Filippo Romanato
(1) Department of Physics and Astronomy ‘G. Galilei’ ,University of Padova, Padova, Italy (2) Laboratory for Nanofabrication of Nanodevices, Padova, Italy
(3) CNR-INFM TASC IOM National Laboratory, Basovizza, Trieste, Italy
The orbital angular momentum (OAM) of light has recently attracted increasing interest, both in academy and industry, due to the possibility offered by its potentially-unbounded state space to manipulate the phase structure and intensity distribution of light beams. Many applications have attracted increasing attention in a wide range of applications: particle trapping and manipulation, nanoscopy, black-hole physics and astronomy, security, and telecom, both in classical and quantum regime.
While several devices and techniques have been designed and experimentally tested for the generation and manipulation of OAM beams, the possibility to integrate many optical operations is still lacking.
Here we present the design and fabrication of innovative optical architectures implementing the multiplexing and sorting of OAM beams with unprecedented levels of compactness and resolution. Samples have been nanofabricated as continuous phase-only diffractive optics with high-resolution electron-beam lithography and tested for the demultiplexing of optical vortex superposition, confirming the high efficiency and resolution.
We have also fabricated metasurfaces in silicon, where nanometric continuos gratings allow to generate birefringence effects and exploiting the Pancharatman-Berry phase delay as design control parameter. We will show how the metasurfaces can be organized in flat metalenses that represent the next frontier for robust industrial up-scalable, aberration-free, wide-bandpass micro optics.
The combination of the design criteria and of the fabrication method generates innovative sorters that are promising to ultimately achieve the required miniaturization and integration levels of high-fidelity OAM beam manipulation, and eventually inspire numerous applications that harness the intriguing properties of twisted light, both in classical and quantum regimes.
Speaker short Bio:
Filippo Romanato is associate professor of physics at the University' of Padua and coordinator of the local group of Nanodevices. Director of LAboratory for Nanofabrication and Nanodevices (LaNN) and Scientific adviser of SM Optics. Since June 1998 he is in charge of the nanofabrication LILIT group at the INFM-CNR laboratory based at the synchrotron Elettra in Trieste. Co-founder of three spin-off dedicated to nanolithography, electronic integration in biosensing, and telecommunication. Coordinator of basic and industrial projects for technological transfer. His research has been devoted originally to structural study of semiconductor materials. Later he specialized in processes nanofabrication and lithographic techniques with particular applications to nano photonics and plasmonics, to biosensors for human genetics and agro-food. He is project manager for the development of tools and nanolithography nano-optics, for the study of the propagation of structured light with orbit al angular momentum applied to the plasmon and fiber telecommunication.
Filippo Romanato
(1) Department of Physics and Astronomy ‘G. Galilei’ ,University of Padova, Padova, Italy (2) Laboratory for Nanofabrication of Nanodevices, Padova, Italy
(3) CNR-INFM TASC IOM National Laboratory, Basovizza, Trieste, Italy
The orbital angular momentum (OAM) of light has recently attracted increasing interest, both in academy and industry, due to the possibility offered by its potentially-unbounded state space to manipulate the phase structure and intensity distribution of light beams. Many applications have attracted increasing attention in a wide range of applications: particle trapping and manipulation, nanoscopy, black-hole physics and astronomy, security, and telecom, both in classical and quantum regime.
While several devices and techniques have been designed and experimentally tested for the generation and manipulation of OAM beams, the possibility to integrate many optical operations is still lacking.
Here we present the design and fabrication of innovative optical architectures implementing the multiplexing and sorting of OAM beams with unprecedented levels of compactness and resolution. Samples have been nanofabricated as continuous phase-only diffractive optics with high-resolution electron-beam lithography and tested for the demultiplexing of optical vortex superposition, confirming the high efficiency and resolution.
We have also fabricated metasurfaces in silicon, where nanometric continuos gratings allow to generate birefringence effects and exploiting the Pancharatman-Berry phase delay as design control parameter. We will show how the metasurfaces can be organized in flat metalenses that represent the next frontier for robust industrial up-scalable, aberration-free, wide-bandpass micro optics.
The combination of the design criteria and of the fabrication method generates innovative sorters that are promising to ultimately achieve the required miniaturization and integration levels of high-fidelity OAM beam manipulation, and eventually inspire numerous applications that harness the intriguing properties of twisted light, both in classical and quantum regimes.
Speaker short Bio:
Filippo Romanato is associate professor of physics at the University' of Padua and coordinator of the local group of Nanodevices. Director of LAboratory for Nanofabrication and Nanodevices (LaNN) and Scientific adviser of SM Optics. Since June 1998 he is in charge of the nanofabrication LILIT group at the INFM-CNR laboratory based at the synchrotron Elettra in Trieste. Co-founder of three spin-off dedicated to nanolithography, electronic integration in biosensing, and telecommunication. Coordinator of basic and industrial projects for technological transfer. His research has been devoted originally to structural study of semiconductor materials. Later he specialized in processes nanofabrication and lithographic techniques with particular applications to nano photonics and plasmonics, to biosensors for human genetics and agro-food. He is project manager for the development of tools and nanolithography nano-optics, for the study of the propagation of structured light with orbit al angular momentum applied to the plasmon and fiber telecommunication.