Conference Agenda

TOM9 S01: Opto-electronic Nanotechnologies and Complex Systems: Plasmonics
Tuesday, 13/Sept/2022:
11:30am - 1:00pm

Session Chair: Vito Mocella, CNR, Italy
Location: B231

2nd floor, 70 seats

11:30am - 12:00pm
ID: 307 / TOM9 S01: 1
TOM 9 Opto-electronic Nanotechnologies and Complex Systems

All-dielectric sensing platform based on bound states in the continuum: biological and healthcare applications

Silvia Romano

CNR, Italy

Large-area and transparent all-dielectric metasurfaces sustaining photonic bound states in the continuum (BICs) provide a set of fundamental advantages for ultrasensitive biosensing. A BIC is a special mode in the energy continuum of free space waves that cannot couple with free-space radiation, which leads to a diverging radiative Q-factor and a topological singularity in the reciprocal space. Here, we present several applications of BICs for surface amplification of fluorescence emission and Raman scattering, biological and chemical sensing with capability of detecting ultralow-weight molecules and protein traces. This approach aims at a precise and ultrasensitive approach for developing low-cost point-of-care tools suitable for routine disease prescreening analyses in laboratory, also adaptable to industrial production control and can be extended to many other applications for studying physical, chemical, and biological processes.

12:00pm - 12:15pm
ID: 264 / TOM9 S01: 2
TOM 9 Opto-electronic Nanotechnologies and Complex Systems

Plasmonic and 2D-TMD nanoarrays for large-scale photon harvesting and enhanced molecular photo-bleaching

Giulio Ferrando1, Matteo Gardella1, Matteo Barelli1, Debsree Chowdhury1, Pham Duy Long2, Nguyen Si Hieu2, Maria Caterina Giordano1, Francesco Buatier De Mongeot1

1Dipartimento di Fisica, Università€ di Genova, Via Dodecaneso 33, I-16146 Genova, Italy; 2Institute of Materials Science, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam

The urgent environmental and energy challenges require novel solutions for efficient light harvesting and conversion in new-generation ultra-thin devices. Plasmonic nanoantennas and flat optics nanogratings can promote light matter interaction at the nanoscale being very attractive for ultra-thin photonics and sensing applications. In this work we developed two light trapping solutions based on large-scale nanomaterials. The first system is a large-scale (cm2) plasmonic metasurface based on self-organized gold nanostripes. The second is based on the periodic re-shaping of ultra-thin semiconducting MoS2 layers forming large-area flat-optics nanogratings. Under this condition Rayleigh Anomalies can be resonantly excited thus promoting in-plane light confinement and photon absorption into the few-layers material. To demonstrate the impact of these nanopatterned systems in photon harvesting we probed their efficiency into a prototypal photochemical reaction: the photo-bleaching of Methylene Blue (MB). We demonstrate the resonant enhancement of the photo-bleaching of these polluting dye molecules promoted either by the localized plasmon resonance in Au nanostripes or by the Rayleigh Anomaly in flat-optics MoS2 nanogratings. We investigate this effect through a quantitative analysis of the solution photodissociation induced by a monochromatic light. These results show the strong potential of flat-optics templates for light-harvesting and energy conversion in ultra-thin photonic devices.

12:15pm - 12:45pm
ID: 346 / TOM9 S01: 3
TOM 9 Opto-electronic Nanotechnologies and Complex Systems

3D Chiral metamaterials for biosensing

Vittorianna Tasco

CNR, Italy

In this contribution we will discuss the experimental application of 3D chiral metamaterials as high sensitivity biosensors, exploiting circular dichroism in transmission. 3D metamaterials with chiral features can be realized by highly accurate and highly localized bottom-up nanofabrication approach. Large chiroptical effects can be engineered, originating from the single element optical resonances, but collective interactions in arrayed configurations can play a significant role, further enhancing these effects. Capability of biomarker detection in the femtomolar range is demonstrated even in complex biofluid matrix.