A5072728312- Photonic and Optical Devices
- Optical Network Technologies
- Advanced Photonic Communication Systems
- Plasmonic and Surface Plasmon Research
- Semiconductor Lasers and Optical Devices
- Thin-Film Transistor Technologies
- Silicon Nanostructures and Photoluminescence
- Semiconductor Quantum Structures and Devices
- Nanowire Synthesis and Applications
- Neural Networks and Reservoir Computing
- Photonic Crystals and Applications
- Mechanical and Optical Resonators
- Graphene research and applications
- Quantum Information and Cryptography
- Advanced Fiber Laser Technologies
- Molecular Junctions and Nanostructures
- Optical Wireless Communication Technologies
- Silicon and Solar Cell Technologies
- Advanced Optical Sensing Technologies
- Quantum Mechanics and Applications
- Semiconductor materials and interfaces
- solar cell performance optimization
- Semiconductor materials and devices
- Quantum Computing Algorithms and Architecture
- Radio Frequency Integrated Circuit Design
Consorzio Nazionale Interuniversitario per le Telecomunicazioni
2014-2024
Scuola Normale Superiore
2023
Roma Tre University
2007-2013
University of Rome Tor Vergata
2012
Institute of Materials for Electronics and Magnetism
2012
National Interuniversity Consortium for the Physical Sciences of Matter
2007-2011
Sapienza University of Rome
2009-2011
We present a micrometer scale, on-chip integrated, plasmonic enhanced graphene photodetector (GPD) for telecom wavelengths operating at zero dark current. The GPD is designed and optimized to directly generate photovoltage has an external responsivity~12.2V/W with 3dB bandwidth~42GHz. utilize Au split-gates a$\sim$100nm gap electrostatically create p-n-junction simultaneously guide surface plasmon polariton gap-mode. This increases light-graphene interaction optical absorption results in...
In this paper we report on an electro-refractive modulator based single or double-layer graphene top of silicon waveguides. The layers are biased to the transparency condition in order achieve phase modulation with negligible amplitude modulation. By means a detailed study both electrical and optical properties silicon, as well through optimization geometrical parameters, show that proposed devices may theoretically outperform existing modulators terms V(π)L insertion losses. overall figures...
Abstract Graphene integrated photonics provides several advantages over conventional Si photonics. Single layer graphene (SLG) enables fast, broadband, and energy-efficient electro-optic modulators, optical switches photodetectors (GPDs), is compatible with any waveguide. The last major barrier to SLG-based receivers lies in the current GPDs’ low responsivity when compared PDs. Here we overcome this by integrating a photo-thermoelectric GPD microring resonator. Under critical coupling,...
Graphene and related materials can lead to disruptive advances in next generation photonics optoelectronics. The challenge is devise growth, transfer fabrication protocols providing high (>5,000 cm2 V-1 s-1) mobility devices with reliable performance at the wafer scale. Here, we present a flow for integration of graphene circuits. This relies on chemical vapour deposition (CVD) single layer (SLG) matrices comprising up ~12000 individual crystals (SCs), grown match geometrical configuration...
One of the main challenges next generation optical communication is to increase available bandwidth while reducing size, cost and power consumption photonic integrated circuits. Graphene has been recently proposed be with silicon photonics meet these goals because its high mobility, fast carrier dynamics ultra-broadband properties. We focus on graphene photodetectors for speed datacom telecom applications based photo-thermo-electric effect, allowing direct voltage conversion, zero dark...
Abstract Electro-absorption (EA) waveguide-coupled modulators are essential building blocks for on-chip optical communications. Compared to state-of-the-art silicon (Si) devices, graphene-based EA promise smaller footprints, larger temperature stability, cost-effective integration and high speeds. However, combining speed large modulation efficiencies in a single device has remained elusive so far. In this work, we overcome fundamental trade-off by demonstrating the 2D-3D dielectric...
We report compact, scalable, high-performance, waveguide integrated graphene-based photodetectors (GPDs) for telecom and datacom applications, not affected by dark current. To exploit the photothermoelectric (PTE) effect, our devices rely on a graphene/polymer/graphene stack with static top split gates. The polymeric dielectric, poly(vinyl alcohol) (PVA), allows us to preserve graphene quality generate controllable p-n junction. Both layers are fabricated using aligned single-crystal arrays...
A circuit for the management of any arbitrary polarization state light is demonstrated on an integrated silicon (Si) photonics platform. This allows us to adapt into standard fundamental TE mode a Si waveguide and, conversely, control and set it state. In addition, thermal tuning kilohertz speed which can be used perform scrambler. The was in WDM link successfully four channels photonic circuit.
Optoelectronics is a valuable solution to scale up wireless links frequency sub-THz in the next generation antenna systems and networks. Here, we propose low-power consumption, small footprint building block for 6 G 5 new radio transmission allowing broadband capacity (e.g., 10-100 Gb/s per link beyond). We demonstrate datalink based on graphene, reaching setup limited carrier multi-Gbit/s data rate. Our device consists of graphene-based integrated optoelectronic mixer capable mixing an...
Graphene is a 2D material with appealing electronic and optoelectronic properties. It zero-bandgap valence conduction bands meeting in single point (Dirac point) the momentum space. Its conductivity can be changed by shifting Fermi level energy via an external electric field. This important property determines broadband tunable absorption at optical frequencies. Moreover, its complex quantity, i.e., exhibits both electro-absorption electro-refraction tunability, this intriguing for photonic...
We discuss thermal evaporation of Germanium thin films as a suitable route to realizing near-infrared detectors integrated on Silicon platform. study the structural properties samples grown at various substrate temperatures by X-ray diffraction and transmission electron microscopy, showing that Ge are amorphous when deposited below 225°C, mono-crystalline between 225 400°C, poly-crystalline above 450°C. further investigate their optical electrical using differential absorption spectroscopy,...
We report for the first time and characterize experimentally complex optical conductivity of graphene on silicon photonic waveguides. This permits us to predict accurately behavior integrated devices encompassing layers. Exploiting a Si microring add/drop resonator, we show effect electrical gating effective index waveguide by measuring both wavelength shift resonance change in drop peak transmission. Due electro-refractive giant (>10-3) is demonstrated photonics waveguides this large will...
In this paper, we report on an optically controlled field effect transistor (OCFET). The device is based a modified MOSFET geometry with Germanium layer interposed between the gate oxide and metal contact. investigation performed using technology computer aided design tool. We describe principle of operation investigate static dynamic properties OCFET under near infrared light at 1.55 μm. Device performance in terms both ON/OFF current ratio switching times are studied versus parameters such...
An integrated silicon-on-insulator microwave photonic phase shifter is demonstrated, based on an optical deinterleaver providing box-like transfer function and a reverse-biased pn-junction waveguide shifter. The circuit proved to precisely control the of signals in range more than 400° with fast reconfiguration time 1 ns, broad bandwidth 6 GHz around RF carrier flexibly selectable between 10 16 GHz, limited in-band power variations. Moreover, thanks periodic behavior deinterleaver, device...
We report on a C-band double layer graphene electro-absorption modulator passive SOI platform showing 29GHz 3dB-bandwith and NRZ eye-diagrams extinction ratios ranging from 1.7 dB at 10 Gb/s to 1.3 50 Gb/s. Such high modulation speed is achieved thanks the quality of CVD pre-patterned single crystal growth transfer wafer method that permitted integration high-quality scalable low contact resistance. By demonstrating this high-speed EAM integrated Si photonics approach, we are confident can...
Using differential optical absorption spectroscopy of germanium thin films epitaxially grown on silicon, we accurately evaluate the near-infrared versus wavelength and temperature. The results allow for optimized design realization Ge-on-Si photodetectors.
Germanium is considered the most suitable semiconductor for monolithic integration of near-infrared detectors on silicon photonic chips. Here we report Ge-on-Si photodetectors fabricated by thermal evaporation, demonstrating use phosphorus spin-on-dopant to compensate acceptor states introduced dislocations. The exhibit 1.55 μm responsivities as high 0.1 A/W, more than two orders magnitude larger in undoped devices and comparing well with state-of-the-art p-i-n photodiodes. This approach...
Adiabatic polarization splitter-rotators are investigated exploiting continuous symmetry breaking thereby achieving significant device size and losses reduction in a single mask fabrication process for both SOI channel ridge waveguides. A crosstalk lower than -25 dB is expected over 300nm bandwidth, making the suitable full grid CWDM diplexer/triplexer FTTH applications at 1310, 1490 1550nm.
We study the frequency chirp properties of graphene-on-silicon electro-absorption modulators (EAMs). By experimentally measuring a 100 µm long single layer graphene EAM, we show that optoelectronic induce large positive linear on optical signal generated by modulator, giving rise to maximum shift instantaneous up 1.8 GHz. exploit this peculiar feature for chromatic-dispersion compensation in fiber optic transmission thanks pulse temporal lensing effect. In particular, dispersion 10Gb/s...
The future envisaged global-scale quantum communication network will comprise various nodes interconnected via optical fibers or free-space channels, depending on the link distance. segment of such a should guarantee certain key requirements, as daytime operation and compatibility with complementary telecom-based fiber infrastructure. In addition, space-to-ground links require capability designing light compact devices to be placed in orbit. For these reasons, investigating available...
We report on Germanium Glass solar cells realized by wafer bonding, layer splitting and epitaxial regrowth.We provide a detailed description of the transfer process discuss material characterization.The are fabricated tested to extract most significant figures merit, evaluating their performance versus device area operating temperature.The exhibit typical conversion efficiencies exceeding 2.4% under AM1.5 irradiation maximum efficiency 3.7% concentrated excitation.This approach is promising...