Nano-Tooling

Structuring matter by ultrafast optical vortex beams

 The crucial role of surface morphology in regulating the properties of a surface accounts for the growing interest in laser surface machining of metals, semiconductors and insulators in view of diverse applications based on the properties of the processed solid surfaces (e.g., optical, mechanical, chemical, biological, wetting, etc.). The use of femtosecond (fs) laser pulses offers advantages in minimizing thermal effects and collateral damage, and the young research field of direct fs laser surface structuring is continuously showing impressive scientific achievements. In most cases, laser beams with a Gaussian intensity spatial profile and spatially homogeneous distribution of polarization are exploited.

However the use of laser beams with a spatially inhomogeneous state of polarization (SoP) is bringing out novel breakthroughs on the horizon of fs laser material processing. Here, by using a simple device invented in our group, we generate different SoP states of an optical vortex beam and demonstrate the fabrication of various regular surface patterns on silicon, including spiral structures as those shown in Figure 1c [1].

nano tools

Figure 1. Examples of the surface structures developed on the silicon target after an irradiation sequence of N = 100 pulses at an energy E0 = 48 μJ with different SoP: (a) radial, (b) azimuthal, (c) spiral and (d) linear. The two panels on the right illustrate the fine morphology of the surface structure for the azimuthal SoP: peripheral regions (yellow box) at the outer edges of the annular OV beam are namely characterised by subwavelength ripples oriented along the normal to the local laser polarization (double-ended arrow), while the internal region of the OV beam (red box) presents microgrooves preferentially directed along the local laser polarization. The fine surface texture observed for the other SoP shows the same characteristic features [1].

Contact Person: Domenico Paparo

[1] Scientific Reports 5, 17929, December 10, 2015, DOI: 10.1038/srep17929.

 

Active accumulation of very diluted biomolecules

A nano-dispenser (pyro-concentrator, PC) able to draw biomolecules from a mother drop and to accumulate them directly onto the surface of a conventional binding substrate was developed[1] opening the possibility of using these tiny droplets for accumulating biomolecules contained in very diluted solutions, pushing the limits of detection down to hundreds of aM. The accumulation effect is achieved directly onto the sample solution by an active mechanism that is free from the time scales of the evaporation effects (as in case of plasmon-based techniques), thus providing a rapid detectability. The nozzle-free modality offers the great advantages of avoiding the dead volume and the clogging issues. Moreover the load volume is in the tenths of microlitre range, contrary to conventional techniques where larger volumes are required (for example, ELISA typically needs 100 ml).

image3

Schematic view of the concentration effect. The red dots represent the analyte molecules, the light blue is the buffer and the pendants on the target slide represent the binding species. The scheme is not to scale

Collaboratori commessa: Veronica Vespini, Sara Coppola, Oriella Gennari

[1]Nature Communications 5, 5314, DOI:10.1038/ncomms6314

 

Electro-drawn biodegradable polymer microneedles

An electro-drawing approach is used for the fabrication of sharp, dissolving microneedles directly from a liquid polymer reservoir, moulding-free and contact-free[1]. Model drugs can be embedded at room temperature in drop reservoirs, drawn to form microneedles at no more than 40 °C and successfully delivered via indentation into the skin. The technique allows for the encapsulation of both hydrophobic and hydrophilic compounds. Microneedle patches are formed directly onto a flexible, disposable strip that is inserted into a cuff, overcoming the technological limitations of both microcasting and drawing  lithography and opening new frontiers in the field of transdermal delivery. In addition, microneedle fabrication is made easy, mould-less, nozzle-less, making way for homemade patches and customized therapies. On-demand and cost-effective microneedles could be obtainable in-situ directly at the point of care, thus replacing the traditional syringes.

image4

magnified and fluorescence image of one electro-drawn microneedleonto a polymer micropillar (scale bar 100 μm); optical confocal image of a slice of the microneedle (scale bar 100 μm);flexible multi-drug therapeutic cuff

Collaboratori commessa: Veronica Vespini, Sara Coppola, Eliana Esposito, Raffaele Vecchione

[1]Advanced Functional Materials ,24,  23,  3515–3523, June 18, 2014 DOI: 10.1002/adfm.201303679

 

Developmental Biology

Central to all activities of the NanoBiomolecular group is a small model organism, at the base of animal evolution, the freshwater polyp Hydra vulgaris. A simple body plan, structured in just two epithelial layers, the unlimited self-renewal and differentiation activity of the stem cell lineages make Hydra a powerful system to study cell stemness and decision making mechanisms, proliferation, and regeneration programs. By using both classical approaches of molecular biology and advanced nanodevices, we perform functional studies aimed to manipulate molecular pathways (i.e. Wnt pathway) playing crucial roles in the animal life. By genetic, chemical and physical manipulation of key signalling components, we aim to understand the genetic programs underlying embryo development and adult homeostasis, with the final goal to achieve their fine control for therapeutic purposes.

Immagine t

Responsabile della commessa: Claudia Tortiglione

Collaboratori commessa: Angela Tino, Alfredo Ambrosone, Valentina Marchesano

Ambrosone A, Marchesano V, Tino A, Hobmayer B, Tortiglione C (2012) Hymyc1 Downregulation Promotes Stem Cell Proliferation in Hydra vulgaris. PLoS ONE 7(1): e30660. doi:10.1371/journal.pone.0030660

Nanomedicine

The unique properties of bioengineered nanomaterials may offer intriguing alternatives to traditional molecular therapeutics. We exploit multiple in vivo and in vitro approaches to test biocompatibility and functionality of smart nanotools designed for biomedical applications such as gene silencing, optical and magnetic hyperthermia, specific and controlled delivery of bioactive molecules. Elegantly combining animal, cell and molecular and biology, this research line dissects internalization routes, intracellular dynamics and functionalities of multi-tailored nanodevices. Nevertheless, owing to the intrinsic physicoschemical properties of advanced nanomaterials, we develop intelligent nanotools able to modulate  specific cell pathways, thus controlling downstream cell functions and decisions in a space and time selective fashion upon remote physical stimulation (e.g. by light or magnetic field).

immaginet1

Responsabile della commessa: Claudia Tortiglione

Collaboratori commessa: Angela Tino, Alfredo Ambrosone, Valentina Marchesano

– João Conde, Ph.D.; Alfredo Ambrosone; Yulán Hernandez; Furong Tian; Mark McCully; Catherine C Berry; Pedro V Baptista; Claudia Tortiglione; Jesus M de la Fuente. 15 years on siRNA delivery: beyond the State-of-the-Art on inorganic nanoparticles for RNAi therapeutics. Nanotoday, in press

Moros M, Ambrosone A, Stepien G, Fabozzi F, Marchesano V, Castaldi A, Tino A, de la Fuente JM, Tortiglione C. Deciphering intracellular events triggered by mild magnetic hyperthermia in vitro and in vivo. Nanomedicine (Lond). 2015 May 11:1-17.

Ambrosone A, del Pino P, Marchesano V, Parak WJ, de la Fuente JM, Tortiglione C.

Gold nanoprisms for photothermal cell ablation in vivo. Nanomedicine (Lond). 2014 Sep;9(13):1913-22. doi: 10.2217/nnm.14.100

Marchesano V, Hernandez Y, Salvenmoser W, Ambrosone A, Tino A, Hobmayer B, de la Fuente JM, Tortiglione C. Imaging inward and outward trafficking of gold nanoparticles in whole animals.

ACS Nano. 2013 Mar 26;7(3):2431-42. doi: 10.1021/nn305747

Conde J, Ambrosone A, Sanz V, Hernandez Y, Marchesano V, Tian F, Child H, Berry CC, Ibarra MR, Baptista PV, Tortiglione C, de la Fuente JM. Design of multifunctional gold nanoparticles for in vitro and in vivo gene silencing. ACS Nano. 2012 Sep 25;6(9):8316-24

Nanoecotoxicology

Concomitant with the fast-growing advances in the synthesis and engineering of nanomaterials, an urgent evaluation of their toxicity on human beings and environment is strongly encouraged by public health organisations. After release to the aquatic environment nanoparticles can be uptaken by planktonic or sediment dwelling invertebrates, and enter the food chain, representing a hazard for wildlife and humans. Despite the in vitro approaches employed for toxicological screening of hazardous compounds, the use of simple and cost-effective living organisms may enormously contribute to solve unanswered questions related to effects of nanomaterials on environment and health. We use Hydra and Nematostella, animal models routinely employed for ecotoxicology due to their sensitivity to pollutants, to thoroughly investigate the toxicity effects of organic and inorganic nanotools and their transgenerational impact, thus providing a primary screening on the safety of nanomaterials for future applications.

immagine t2

Responsabile della commessa: Claudia Tortiglione

Collaboratori commessa: Angela Tino, Alfredo Ambrosone, Valentina Marchesano

– Ambrosone A, Marchesano V, Mazzarella V, Tortiglione C. Nanotoxicology using the sea anemone Nematostella vectensis: from developmental toxicity to genotoxicology. Nanotoxicology. 2014 Aug;8(5):508-20. doi: 10.3109/17435390.2013.802386.

– Ambrosone A, Scotto di Vettimo MR, Malvindi MA, Roopin M, Levy O, Marchesano V, Pompa PP, Tortiglione C, Tino A. Impact of Amorphous SiO2 Nanoparticles on a Living Organism: Morphological, Behavioral, and Molecular Biology Implications. Front Bioeng Biotechnol. 2014 Sep 29;2:37. doi: 10.3389/fbioe.2014.00037

– Ambrosone A, Mattera L, Marchesano V, Quarta A, Susha AS, Tino A, Rogach AL, Tortiglione C. Mechanisms underlying toxicity induced by CdTe quantum dots determined in an invertebrate model organism. Biomaterials. 2012 Mar;33(7):1991-2000. doi: 10.1016/j.biomaterials.2011.11.041

SQUID sensors for high sensitive applications

The group’s activity is focused on the development of superconducting devices mainly based on Josephson effect. The research core is represented by the Superconducting QUantum Interference Device (SQUID). Due to the low operating temperature and the quantum working principle, it is the most sensitive magnetic flux and field detector known so far, having an equivalent energy sensitivity limited only by quantum effects (uncertainty principle). Thanks to their unique characteristics, SQUIDs are successfully employed in numerous applications requiring an ultra  high sensitive. The group, over the years, has designed and realized SQUID devices in different configurations and used them for biomagnetism or nanomagnetism as well as magnetic microscopy or in current sensing noise thermometry.

vettoliere

Three-dimensional spin nanosensor based on reliable tunnel Josephson nano-junctions for nanomagnetism investigations

vettoliere2

Multisensorial array including 163 SQUID magnetometers for magnetoencephalography

Contact person: Carmine Granata

People: Antonio Vettoliere, Roberto Monaco, Berardo Ruggiero.

Publications

An integrated superconductive magnetic nanosensor for high-sensitivity nanoscale applications

C Granata, E Esposito, A Vettoliere, L Petti, M Russo

Nanotechnology 19 (27), 275501 (2008)

Noise theory of dc nano-SQUIDs based on Dayem nanobridges

C Granata, A Vettoliere, M Russo, B Ruggiero

Physical Review B 84, 224516 (2011)

Three-dimensional spin nanosensor based on reliable tunnel Josephson nano-junctions for nanomagnetism investigations

C Granata, A Vettoliere, R Russo, M Fretto, N De Leo, V Lacquaniti

Applied Physics Letters 103 (10), 102602 (2013)

Bias current ramp rate dependence of the crossover temperature from Kramers to phase diffusion switching in moderately damped NbN/AlN/NbN Josephson junctions

M Lisitskiy, D Massarotti, L Galletti, L Longobardi, G Rotoli, M Russo, F Tafuri, B Ruggiero

Journal of Applied Physics 116 (4), 043905 (2014)

Vertical nano superconducting quantum interference device based on Josepshon tunnel nanojunctions for small spin cluster detection

C Granata, A Vettoliere, M Fretto, N De Leo, L Vincenzo

Journal of Magnetism and Magnetic Materials 384, 117-121 (2015)

Nanostructured highly conductive PEDOT:PSS films with 2D photonic crystals and quasi crystals for efficient OLED and WOLED devices 

Our group together with ENEA UTTP-NANO Laboratory in Portici Research Centre (Carla Minarini’s team), has introduced for the first time an effective process based on the combination of Electron Beam Lithography and Plasma Etching techniques to fabricate a novel polymeric anode structure based on 2D nanopatterned highly conductive PEDOT:PSS layers. Our proposed ITO-free electrode structure can improve the outcoupling efficiency of OLEDs and demonstrate the great potential of PC-polymeric anodes for use in a wide variety of high-performance flexible organic optoelectronics. A 2D nanopatterned transparent anode was also fabricated onto a flexible polyethylene terephthalate (PET) substrate and it was integrated into an organic light emitting diode (OLED). The obtained results fully confirm the feasibility of the developed process of micro/nano patterning PEDOT:PSS.

petti 1

petti2

SEM images (up), light extracted (bottom) and schematic diagram-process (right) of the highly conductive PEDOT:PSS-PQC nanostructured films.

petti3

Photo of light extracted from air-cylinders PCs in polymer with diameter D= 180nm and increasing periods a = 265, 295, 325, 360, 410 nm from left to right.  A white light is introduced from an edge of the glass and propagates inside the glass

Responsabile della commessa: Lucia Petti

Collaboratori della commessa: Massimo Rippa, Giuseppe Nenna, Carla Minarini

 Projects

  • NDA AGREEMENT between ICIB-CNR (PI: L. Petti), Novaled and ENEA (ENEA Portici Research Centre, Section “Nanomaterials and Device Technology”, PI: G. Nenna): “The Parties desire to explore or examine a possible business relationship between them relating to exchange and evaluation of information on OLED technology and OLED materials between the Parties (Purpose: In this project we propose to explore the possibility to use the Organic Light Emitting Diodes (OLED) embedded with Photonic Quasi Crystal (PQC) structures to achieve an enhancement in the device efficiency)”. Duration: 2013-2016
  • Project title: RELIGHT- Research for LIGHT (lighting and sunlight), (PON02_00556_3306937, CUP I2IJ2000040005). Funded by: MIUR. Duration: 2013-2015. PI for CNR: L. Petti. [Total budget to CNR 165.000 Euro].

Articles in peer-reviewed journals

  1. Nanostructured PEDOT:PSS film with Two-dimensional Photonic Quasi Crystals for Efficient White OLED Devices. Massimo Rippa, Rossella Capasso, Lucia Petti, Giuseppe Nenna, Anna De Girolamo Del Mauro, Maria Grazia Maglione and Carla Minarini. Mater. Chem. C, 3 (1), 147–152, (2015). DOI: 10.1039/c4tc01936a.
  2. Photonic quasi crystals to enhance light extraction efficiency for white OLEDs applications. Massimo Rippa, Rossella Capasso, Lucia Petti (ICIB-CNR) Giuseppe Nenna, Anna De Girolamo Del Mauro, Maria Grazia Maglione, M. Della noce and Carla Minarini (UTTP Enea). IEEE Conference Publications Program (CPP), 2014 Fotonica AEIT Italian Conference on Photonics Technologies, Fotonica AEIT 2014 6843848 (2014)
  3. Novel Organic LED Structures based on Highly Conductive Polymeric Photonic Crystal Electrode. Lucia Petti, Massimo Rippa, Rossella Capasso, Giuseppe Nenna, Anna De Girolamo Del Mauro, Maria Grazia Maglione and Carla Minarini. Nanotechnology 24 (31), art. no. 315206 (2013). ISSN: 09574484. DOI: 10.1088/0957-4484/24/31/315206.
  4. Fabrication of Novel Two-dimensional Nanopatterned Conductive PEDOT:PSS Films for Organic Optoelectronic Applications. Lucia Petti, Massimo Rippa, Rossella Capasso, Giuseppe Nenna, Anna De Girolamo Del Mauro, Giuseppe Pandolfi, and Carla Minarini. ACS Applied Materials & Interfaces 5 (11), pp. 4777-4782 (2013). ISSN: 19448244. DOI: 10.1021/am401451r.
  5. Photonic crystal electrode to be used in organic LED structures. Lucia Petti, Massimo Rippa, Rossella Capasso, Giuseppe Nenna, Anna De Girolamo Del Mauro, Vera La Ferrara, Aneesh Pacheri Madathil, Carla Minarini. Europ. Opt. Soc. Rap. Public. 8, 13002 (2013). ISSN: 19902573. DOI: 10.2971/jeos.2013.13002.

Novel active organic/inorganic photonic crystal (PC) and quasi crystals (PCs) for light emitting devices

New generation materials “under construction” should enhance the performance of photonic devices and broaden their applications, which usually means improving functionality and reducing cost. Tremendous innovations are expected from polymer coatings that exhibit superior functional properties at low cost. One option is to include nanoparticles in the polymer matrix. The challenge is to avoid phase separation, aggregation of nanoparticles and loss of transparency.

We prepared high transparent and luminescent nanocomposites by incorporating colloidal semiconductor quantum rods of nanometer size scale into polymer matrices. Shortly afterwards, we patterned such nanocomposites to fabricate novel large area 2D Active photonic crystal (PC) and quasi crystal (PQC) slabs. The picture shows an example of a patterned nanocomposite with different hybrid organic/inorganic PCs and PQCs. A white light is introduced from an edge of the glass and is propagating inside the glass. The PC and PQCs areas are seen as colored areas because of the wavelength-selective diffraction by the hybrid Photonic structures.

petti4

Sample of glass coated with a nano composite which has been patterned with different nanostructures (PCs and photonic quasi crystals. On the right corners the SEM image (bottom) and the measured far diffraction pattern (top), on the left corner extracted spectrum from a PQC are reported, respectively.

petti5

petti6

THUE-MORSE M10

petti14

Far Field Diffraction by Supercontinuum White Laser showing Colorimetric Fingerprints

petti15

Far Field Diffraction by OPSL Laser showing a singular continuous Fourier spectrum

Responsabile della commessa: Lucia Petti

Collaboratori della commessa: Massimo Rippa

 Articles in peer-reviewed journals

  1. Bragg extraction and diffraction properties of active organic/inorganic 2D dodecagonal photonic quasi-crystals. Massimo Rippa, Sergio De Nicola, Rossella Capasso, Pasquale Mormile, Jun Zhou and Lucia Petti. Science of Advanced Materials 6, pp. 1–7, (2014).
  2. Bragg Extraction of Light in 2D Photonic Thue Morse Quasicrystal patterned in Active CdSe/CdS Nanorods-Polymer Nanocomposites. Massimo Rippa, Rossella Capasso, Pasquale Mormile, Sergio De Nicola, Marco Zanella, Liberato Manna, Giuseppe Nenna and Lucia Petti. Nanoscale, 2013, 5, 331. ISSN: 20403364. DOI: 10.1039/c2nr31839c.
  3. CdSe/CdS nanorods-polymer nanocomposites patternable by e-beam lithography: A novel active 2D photonic quasicrystal simulated, designed, fabricated and characterized . PETTI, M Rippa, R Capasso, M Zanella, L Manna, and P Mormile. AIP Conf. Proc. 1459, pp. 154-156 (2012); doi:http://dx.doi.org/10.1063/1.4738428.
  4. Novel hybrid organic/inorganic 2D photonic quasicrystals with 8-fold and 12-fold diffraction symmetries. PETTI, M Rippa, R Capasso, M Zanella, J Zhou, and P Mormile. Proc. SPIE 8409, 84091E (April 2, 2012); doi:10.1117/12.923183.
  5. The effect of lattice shapes of Thue-Morse crystals on the diffraction pattern. Feng, Y.-P., Zhou, J., Petti, L., Yang, M.-Y., Zhang, L.-F., Ma, Y.-Q. Guangdian Gongcheng/Opto Engineering 38 (11), pp. 130-135 (2011).
  6. Fabrication and Optical Properties of Two-dimensional Thue-Morse Quasicrystals. Feng, Y.-P., Zhou, J., Petti, L., Yang, M.-Y., Hao, L., Haifang D. Acta Optica Sinica 31 (4) , pp. 0423001-1 (2011).
  7. Fractals characteristics of far-field diffraction patterns for two-dimensional Thue-Morse quasicrystals. Mingyang Yang, Jun Zhou, L Petti, S De Nicola, P Mormile. Optoelectronics Letters, 7, 5 (2011). DOI 10.1007/s11801-011-1057-0.
  8. A non-iterative image reconstruction method based on the subtraction of diffraction-intensity pattern. Jun Zhou, Mingyang Yang, L Petti, P Mormile. Optical Engineering 50, 11 (November 2011).
  9. A Novel hybrid organic/inorganic photonic crystal slab showing a resonance action at the Band Edge. L Petti, M Rippa, J Zhou, L Manna and P Mormile. Nanotechnology 22 285307 (2011). DOI:10.1088/0957-4484/22/28/285307.
  10. Novel hybrid organic/inorganic 2D Quasiperiodic PC: from diffraction pattern to vertical light extraction. Lucia Petti, Massimo Rippa, Jun Zhou, Liberato Manna, Marco Zanella and Pasquale Mormile. Nanoscale Research Letters 2011, 6:371 (4 May 2011). DOI:10.1186/1556-276X-6-371.
  11. Spectral characterization of two-dimensional Thue-Morse quasicrystals realized with high resolution lithography. Matarazzo, S. De Nicola, G. Zito, P. Mormile, M. Rippa, G. Abbate, J. Zhou, and L. Petti. Journal of Optics, 13, 015602 (2011). DOI: 10.1088/2040-8978/13/1/015602.

Photonic Crystals and Photonic Quasi-Crystals for LSPR and SERS nanobiosensing

The possibility of engineering complex metal nanoparticle arrays with distinctive plasmonic resonances extending across the entire visible spectrum can have a significant impact on the design and fabrication of novel nanodevices based on broadband plasmonic enhancement. With the use of PCs and PQCs, it is possible to synthesize novel artificial structures characterized by highly selective, sensitive, tunable in frequency EM response with significative amplification of the surface-enhanced Raman scattering (SERS) signal in presence of specific analytes. Our Team developed innovative plasmonic nanobiosensors based on both LSPR and SERS working in the visible frequency band. SERS on PQC arrays with precisely controlled size and spacing fabricated via electron beam lithography were investigated. The SERS substrates show high efficiency at 785 nm excitation in the detection of p-mercaptoaniline (pMA), and a SERS enhancement factor (EF) of 107 is achieved.

petti 16  petti 17petti 18

Responsabile della commessa: Lucia Petti

Collaboratori della commessa: Pasquale Mormile, Massimo Rippa, Jun Zhou, Riccardo Castagna

  Projects

  • Project title: Kit for Brucella Abortus e B. Melitensis nano-BIosensing RApid detection (AMBRA). Funded by FESR P.O.R. Campania 2007-20013 – BANDO SPORTELLO DELL’INNOVAZIONE – PROGETTI DI TRASFERIMENTO TECNOLOGICO COOPERATIVI E DI PRIMA INDUSTRIALIZZAZIONE PER LE IMPRESE INNOVATIVE AD ALTO POTENZIALE. Duration: 2014-2015. PI: L. Petti.
  • Project title: Study on the immunological detection technology of tumor marker based on SERS characteristics of gold nanoparticle array. Funded by: National Nature Science Found of China (Major International Joint Research Project, Project grant number 601320106014). Duration: 01/2014-12/2018. PI: L. Petti. [Total budget 2.900.000 RMB-408.000 Euro].

 Articles in peer-reviewed journals

  1. Au@Ag Core-Shell Nanocubes: Epitaxial Growth Synthesis and Surface-Enhanced Raman Scattering Performance. Yanting Liu, Jun Zhou, Binbing Wang, Tao Jiang, H.P. Ho, Lucia Petti and Pasquale Mormile. Physical Chemistry Chemical Physics, (2015). DOI: 10.1039/C4CP05642F.
  2. Plasmonic Octagonal Quasi Crystals for Surface-Enhanced Raman Sensing. Lucia Petti, Rossella Capasso, Massimo Rippa, Jun Zhou, Maria Grazia Maglione, Marianna Pannico, Pietro La Manna and Pellegrino Musto. Advanced Device Materials, (2015)
  3. Controllable synthesis and SERS characteristic of hollow sea urchin gold nanoparticles. Li, J. Zhou, T. Jiang, B. Wang, M. Gu, L. Petti and P. Mormile, Phys. Chem. Chem. Phys., 16, 46, 25601-25608 (2014). DOI: 10.1039/c4cp04017a
  4. Highly Sensitive Immunoassay Based on SERS Using Nano-Au Immune Probes and a Nano-Ag Immune Substrate. Lei Shu, Jun Zhou, Xiaocong Yuan, Lucia Petti, Jinping Chen, Zhenhong Jia, Pasquale Mormile. Talanta, 123, 161–168, (2014)
  5. Localized surface plasmon resonance and surface enhanced raman scattering responses of Au@Ag core-shell nanorods with different thickness of Ag shell. Yanan Ma, Jun Zhou, Weibo Zou, Zhenhong Jia, Lucia Petti and Pasquale Mormile. Journal of Nanoscience and Nanotechnology, 14 (6), pp. 4245-4250, (2014)
  6. Optimizing Au/Ag core–shell nanorods: purification, stability, and surface modification. Yanan Ma, Jun Zhou, Lei Shu, Tianhua Li, Lucia Petti and Pasquale Mormile. Journal of Nanoparticle Research, 16, 2439, (2014). DOI: 10.1007/S11051-014-2439-6

Switchable Photonic Devices based on Nanocomposites and Reconfigurable Optical  Metamaterials (Photonic Crystals – Dispersed Liquid Crystalline Metamaterials)

Fabricating MTMs that are reconfigurable/switchable, represents a new challenge. In fact, switching and tuning of the MTMs electromagnetic response is gaining scientific interests as a natural research development to attain functionalities in MTMs. Dynamically modulating the dielectric properties of the medium surrounding the MTMs has attracted interest in photonic field applications; in this framework, Liquid Crystals (LCs) have been recently examined, as their local refractive index can be easily modified by using electrical and thermal stimuli. Our Team, in collaboration with Prof. Cesare Umeton’s Team from University of Calabria, realized and characterized a switchable photonic device, working in the visible range, based on nanostructured metal Thue-Morse (ThMo) PQCs, layered with photo-responsive LCs (PLC). Both experimental characterization and numerical simulations show that excitation spectra can be controlled by applying an external voltage or by means of a laser light: white light propagating in the glass substrate is out-coupled through Bragg diffraction from the PQC according to its geometrical parameters; when the PLC is incorporated, the resulting PQC- PLC cell structure works as a single photonic device, where the wavelength-selective light extraction can be controlled by external stimuli (electric field, optical field). In addition, for the first time, to the best of our knowledge, the LC alignment on a nanoscale complex 2D pattern is also demonstrated.

petti19  petti20  petti21

Responsabile della commessa: Lucia Petti

Collaboratori della commessa: Massimo Rippa

Articles in peer-reviewed journals

  1. Tunable Bragg Extraction of Light in Photonic Quasi Crystals – Dispersed Liquid Crystalline Metamaterials. Massimo Rippa, Rossella Capasso, Cesare Umeton, Lucia Petti. SPIE optics + Photonics 2015 (Invited Talk), San Diego 9-13 agosto 2015.
  2. Electro/All Optical Light Extraction in Gold Photonic Quasi-Crystals Layered with Photosensitive Liquid Crystals. Vincenzo Caligiuri+, Luciano De Sio+, Lucia Petti+, Rossella Capasso, Massimo Rippa, Maria Grazia Maglione, Nelson Tabiryan and Cesare Umeton*. Advanced Optical Materials, 2: 950–955. DOI: 1002/adom.201400203 (2014).
  3. Electro-Optic Tuning in Photonic Crystals – Dispersed Liquid Crystalline Metamaterials. M Rippa, P Mormile, R Capasso, M Zanella and L PETTI. Molecular Crystals and Liquid Crystals 573 (1), 18-25 (2013). ISSN: 15421406. DOI:10.1080/15421406.2013.763333.

Chiral NLO meta-molecules

New chiroptical experimental schemes allowing for the local control of the polarization states of light are being actively searched. Nanoplasmonic structures and meta-materials are appealing candidates towards on-demand field engineering that could have an impact on biochemistry towards e.g. biosensors with enantiomer selectivity, nanoscale chiral recognition and (bio-)material sciences. In strong collaboration with Prof. Joseph Zyss’ Team (LPQM-Cachan) who leads this new research field, we study, 2-D non-centrosymetric chiral gold nanostructures (see fig.1), that exhibit a giant chiroptical second harmonic response (C-SHG). In the case of nano-plasmonics, the shape and dimensions of tailored nanostructures determines both the resonant modes and eventual hot spots, at the origin, of possible SHG enhancement, depending on their local symmetry. Nano-assemblies of non-centrosymmetric triangular gold nanoparticles are obtained by e-beam lithography and the particles are arranged in quadruplets with respectively left- or right-handed chirality (see fig. 2), at close enough positions that allow for localized plasmon mode coupling, thus forming a plasmonic molecule, with pattern parameters smaller than the excitation wavelength. Such structures could find interesting application in watermarking, as our early demonstration suggests.

petti20

petti30

Fig.1: Examples of “meta-octupoles”, composed of octupolar arrangements of “meta-atoms” also of octupolar symmetry: chiral octupolar meta-molecules made of Gold nano-particles arranged in arrays, and shown to display an enhanced nonlinear chiroptical effect.

petti31

Fig.2: Left, SEM images of gold nanostructures constituting “left” and “right” chiral plasmonic molecules. Centre, SEM image of an array of plasmonic molecules, “right” and “left”, forming a “R” shaped pattern. Right, SHG microscopy image of the array excited with circularly polarized light. SHG circular dichroism uniquely allows to retrieve the encoded “R” pattern.

Responsabile della commessa: Lucia Petti

Collaboratori della commessa: Joseph Zyss, Massimo Rippa

 Articles in peer-reviewed journals and International conferences

  1. Octupolar plasmonic meta-molecules for nonlinear chiral watermarking at subwavelentgh scale. Radoslaw Kolkowski Lucia Petti, Massimo Rippa, Clement Lafargue, and Joseph Zyss. In print on ACS Photonics (2015).
  2. Nano-scale engineering and nonlinear imaging of chiral plasmonic assemblies. Radoslaw Kolkowski Lucia Petti, Massimo Rippa, Clement Lafargue, and Joseph Zyss. Frisno-13, Aussois, France. 17-22 Marzo 2015.
  3. Nano-plasmonic chiral S.H.G. emitters. Radoslaw Kolkowski, Lucia Petti, Massimo Rippa, Clement Lafargue, and Joseph Zyss. Cleo’2015.
  4. From Molecules to Meta-Molecules: A nano-plasmonic revival of multipolar molecular engineering for NL. Radoslaw Kolkowski, Clement Lafargue, Benjamin Dwir, Eli Kapon, Massimo Rippa, Lucia Petti, and Joseph Zyss. 12th Mediterranean Worshop and Topical Meeting “Novel Optical Materials and Applications-NOMA 2015, 7-13 Giugno 2015.