Skip to content

Andrea Di Falco

Optical neural networks based on perovskite solar cells

We are excited to announce the publication of our latest research, which introduces a novel approach to Optical Neural Networks (ONNs)—computing platforms that utilize light to perform ultra-fast, energy-efficient computations. Traditionally, ONNs rely on CCD cameras to capture output signals, but our study explores a promising alternative: perovskite solar cells. Our findings demonstrate that solar-cell-based ONNs not only match but outperform CCD-based systems of the same resolution. Thanks to their large acquisition area, high efficiency, and ability to generate signals without amplification, perovskite solar cells present a scalable, cost-effective solution for ONN output detection. This breakthrough paves the way for automated, battery-free edge-computing applications, offering… Read More »Optical neural networks based on perovskite solar cells

Machine-learning-assisted dual harmonic generation FROG for enhanced ultrafast pulse recovery

We are excited to announce the publication of a new study that enhances the characterization of ultrafast pulses, essential for exploring phenomena at femtosecond timescales. The research, led by Ferrera’s group, introduces an innovative encoder-decoder machine learning framework for the Frequency-Resolved Optical Gating (FROG) system, utilizing dual harmonic generation in low-index thin films. This approach overcomes traditional FROG limitations—such as high computational demands and reliability issues—by leveraging the combined analysis of second and third-harmonic signals. The results show improved accuracy and robustness compared to machine learning techniques relying on single harmonic signals, highlighting the power of contextual information integration.

AR glasses

See-Through Conformable Holographic Metasurface Patches for Augmented Reality

Current requirements for augmented reality (AR) applications demand the use of dedicated AR glasses, which often need custom prescription lenses or contact lenses to correct common visual impairments, thus limiting AR’s broader experiences. In this paper, published in Laser and Photonics Review, we present an innovative methodology for the design, fabrication, and comprehensive analysis of a flexible, reflective-type holographic metasurface patch designed for AR applications. By fabricating a conformable metasurface on a transparent and flexible substrate, we created a prototype of an AR system capable of transforming everyday eyewear into AR glasses.

Distributed photovoltaic neural networks for environmental monitoring – ARIA seed grant awarded

We are very excited to announce that our proposal to develop distributed photovoltaic Neural Networks for cloud monitoring applications has been selected for funding by ARIA. Our project is one of the seed grants selected for funding under the Scoping Our Planet opportunity space. Our team will concentrate on creating a machine learning-based technological platform that utilizes light from both natural and artificial sources while capitalizing on both new and existing solar panel installations for environmental monitoring.

HAZGUARD – ERC Proof of Concept awarded

We are delighted to share that a new Proof of Concept grant associated with the ERC project AMPHIBIANS has started. HAZGUARD stands at the forefront of technological innovation that could significantly alter the landscape of augmented reality (AR) and wearable technology. Its ambition lies in harnessing the potential of holographic metasurface technology to transform standard eyewear into AR-enabled devices. This leap forward promises to democratize AR, making it accessible and practical for a broad audience, including individuals with visual impairments, thereby opening new avenues for interaction, education, and assistance in daily activities.

Meta-Optics for Augmented Reality Applications

In this contribution to the “Roadmap to Photonics Metasurfaces” published in Applied Physics Letters, we critically discuss the opportunities and challenges of using photonic metasurfaces in augmented reality (AR) applications. We briefly summarize the state-of-the-art of AR systems and put forward the hypothesis that meta-optics are already being used in commercial implementations of AR glasses. We then speculate how future systems will embed metasurface technology even further. 

Engineering Waveguide Nonlinear Effective Length via Low Index Thin Films

The nonlinear response of an integrated optical device should take into account the propagation distance relevant to the device. In this paper, we present a CMOS-compatible integrated optical platform with an optimized nonlinear response for propagation lengths of tens of microns. The platform is based on a low-index thin film, interfaced with a silicon-on-insulator guiding layer. The experimental results enable the development of integrated optical networks with low-power nonlinear activation functions.

Self-calibrated flexible holographic curvature sensor

Optical curvature sensors find regular use in deformation analysis, typically requiring pre-calibration and post–processing of gathered data. In this paper, we present a self-calibrated curvature sensor based on flexible holographic metasurfaces operating in the visible range. In contrast to existing solutions, the sensor can be fabricated independently from target objects and provides an immediate readout of their curvature. The sensor consists of distinct patterned areas that create images of a reference scale and of a position indicator, which shift with respect to each other, as the metasurface is deformed. We validate the results of our sensor with an external calibration and critically discuss the types… Read More »Self-calibrated flexible holographic curvature sensor

ZrO2 metasurface

ZrO2 Holographic Metasurfaces for Efficient Optical Trapping in The Visible Range

In this paper, we introduce a new material platform for holographic metasurfaces. Ceramic-based metasurfaces are ideally suited for biophotonic applications, where the operating wavelength goes down to the blue region of the visible range and below. Here, we exploit the unique properties of this platform by demonstrating the first on-chip trapping using blue light.

Optically Manipulated Micromirrors for Precise Excitation of WGM Microlasers

Whispering gallery mode microlasers are highly-sensitive refractive index sensors that are widely explored for biophotonic and biomedical applications. These microlasers are used for excitation and collection of the emitted light, typically utilizing microscope objectives at normal incidence. However, this limits the choice of the oscillation plane of the modes. To overcome this limitation, in this paper, we present a new platform that enables the excitation of microlasers from various directions using an optically manipulated micromirror. This scheme enables precise sensing of the environment surrounding the microlasers along different well-controlled planes. Furthermore, the platform’s capability to perform a time-resolved experiment of dynamic sensing using a polystyrene… Read More »Optically Manipulated Micromirrors for Precise Excitation of WGM Microlasers