Nanotechnology congress & Expo August 11-13, 2015 Frankfurt, Germany

Biography:

Masayoshi Tonouchi received the Dr. E. degrees form Osaka University in 1988. From 1988 to 1996 he worked at Osaka University, Kyushu Institute of Technology, Communications Research Laboratory. From 2000, he has been a professor of Osaka University and a concurrent professor of Nanjing University since 2005. His current research interests include ultrafast optical and terahertz science of strongly correlated electron systems, optical interfaces for single-flux-quantum circuits, and development-and-applications of terahertz systems such as the laser terahertz emission microscope. He is a member of the Optical Society of America, the Japan Society of Applied Physics, the Physical Society of Japan.

Abstract:

Recent progress on terahertz (THz) science and technology attracts much attention to scientists in broad area but also to the general public for new applications . THz waves covers around from 300GHz to 30THz in frequency, which corresponds to 10m to 1mm in wavelength. The values are vastly larger than nanoscales. Nevertheless, we’ve been proposing to create new scientific field as terahertz nanoscience. This is because the links between THz science and nanoscience are so strong. Examples are THz quantum cascade lasers (QCLs), ultrafast carrier dynamics in solids, hydration dynamics in biomolecules and medicines, and so on. THz QCLs are strong THz source and made of multiple layers of quantum wells viz. nanostructure. Various kinds of carrier scattering times in solid state for electronics application distributes from several ten femtoseconds to a few picoseconds whereas 1THz corresponds to 1ps. Hydration time to some molecules are also in similar time scales. Typical energy for intermolecular interaction of large molecules lies in the range of meV, which also corresponds to THz region. In the present work, we give an overview of THz nanoscience and recent progress of our own research such as laser THz emission microscope.

Biography:

Iwao Kawayama received the B. S., M. S. and D. S. degrees in chemistry from Osaka University in 1995, 1997 and 2000, respectively. During 2000-2001, he stayed in RIKEN as a postdoctoral fellow. In 2001, he joined Research Center for Superconductor Photonics in Osaka University, and this center was merged with the Institute of Laser Engineering in 2004. His research interests include development of terahertz photonic devices with superconductors, semiconductors and nanomaterials.

Abstract:

Electrical and optical properties of two-dimensional (2D) materials are known to be affected by the adsorption of gas molecules, which can be used for developing a highly sensitive gas sensor. Thus, any device design using 2D nanomaterials has to take into consideration absorbed gas molecules, and device performance needs to be evaluated in terms of environmental influence. In this study, we observed absorption and desorption dynamics on 2D nanomaterials such as graphene and WS2 using laser terahertz emission spectroscopy (LTES) and terahertz time-domain spectroscopy (THz-TDS). We found that the waveforms of terahertz radiation from 2D nanomaterial-coated semiconductors sensitively change with the type of the atmospheric gas and the laser illumination time [1]. The change of the terahertz waveforms in different environmental gases can be explained by modification of the surface depletion-layer potential of semiconductors due to the surface dipole induced by the adsorbed gas molecules. Moreover, additional UV light illumination enhances the change of terahertz waveforms in oxygen, apparently due to photo-oxidation of 2D nanomaterials. We also performed terahertz time-domain spectroscopy study of graphene on various terahertz-transparent substrates at various temperatures. We found that the terahertz optical conductivity spectrum changed owing to molecular desorption from graphene. I will discuss detailed experimental results and potential of terahertz spectroscopy as an evaluation tool for 2D nanomaterials.

Biography:

Stephane Boubanga Tombet received his PhD degree in condensed matter physics from Montpellier 2 University in 2008. From 2008 to 2009, he worked for Montpellier 2 University as a teacher and research assistant. From 2009 to 2011, he joined the Research Institute of Electrical Communication (RIEC), Tohoku University, as a postdoctoral researcher. He worked at Los Alamos National Labs as a postdoctoral researcher until Jun 2013. He is currently working as an Associate Professor at the RIEC, Tohoku University. His current research interests include III-V based plasmonics THz emitters and receivers, gaphene active plasmonics and their terahertz applications.

Abstract:

This paper reviews recent advances in the development of plasmon-resonant terahertz (THz) emitters and detectors and their THz system applications. Two-dimensional (2D) plasmon resonance is introduced as the operation principle for broadband emission and detection of THz radiation. Two-dimensional plasmons in submicron transistors have attracted much attention due to their ability to promote emission and detection of electromagnetic radiation in THz range. Coherent plasmonic THz emission can be obtained by the plasma wave instability mechanisms like Dyakonov–Shur Doppler-shift model, but it suffers from incoherent broadband emission at 300K originated from thermally excited hot plasmons. On the other hand, hydrodynamic nonlinearities of 2D plasmons in high-electron-mobility transistors (HEMTs) are promising for fast and sensitive rectification/detection of THz radiation, which are suffering, however, from poor sensitivity in the case of grating-gate-type broadband antenna structures. In order to cope with these problems, we propose an asymmetric, chirped-dual-grating-gate (AC-DGG) HEMT structure. In comparison with conventional symmetric DGG structure, the asymmetric DGG exhibits substantially improved sensitivity and emissivity. Excellent THz emission and detection performances including coherent monochromatic emission at frequencies above 1 THz and the record detection responsivity of 6.4 kV/W at 1 THz and 21.5 kV/W at 0.3 THz were experimentally demonstrated. The fabricated AC-DGG HEMT detectors were used for nondestructive material evaluations based on THz imaging successfully reproducing the 2D images of the inside of an IC card, soap bars in a plastic bag, etc.

Biography:

Dmitry Turchinovich received his PhD in Physics from the University of Freiburg in 2004. After a post-doctoral stay at Utrecht University he moved to Technical University of Denmark, where he was faculty until 2014. Since 2012 Dr. Turchinovich is heading the “Ultrafast dynamics and Terahertz spectroscopy” research group at Max Planck Institute for Polymer Research in Mainz, Germany. Dmitry Turchinovich has published over 35 journal papers and serves on the committees of several international conferences. Dr. Turchinovich is a recipient of several prestigious grants such as Gottfried Daimler- und Karl Benz Stiftung Fellowship and European Union Career Integration Grant.

Abstract:

In this presentation we will review the electron dynamics in graphene subject to ultrafast, picosecond-timescale electrical signals [1-4]. The conduction properties of graphene in such ultrafast fields, corresponding to terahertz (THz) field oscillation frequencies, is crucial for understanding and prediction of graphene performance in ultra-high-speed (opto-)electronic devices such as THz transistors, modulators, detectors etc. The physical picture of ultrafast (photo-)conduction in graphene will be presented, and its consequences for graphene performance in various ultra-high-speed electronics applications will be discussed.

Biography:

Max Eisele has been working since 2011 as a PhD student in the group of Rupert Huber at the University of Regensburg, where he has developed a novel ultrafast microscope tracing femtosecond dynamics of low-energy elementary excitations at the surface of nanometer-sized solids. Max Eisele studied physics at the Technical University of Munich and at the Max Planck Institute of Quantum Optics, where he worked on femtosecond electron emission from sharp metal tips.

Abstract:

Understanding the underlying physical properties of solid state systems has always been the key challenge in disentangling the origins of complex emergent phenomena like high-temperature superconductivity, insulator-to-metal phase transitions and charge density waves. Such effects strongly depend on the precise interplay between low-energy excitations such as phonons, excitons and plasmons. The development of terahertz time-domain spectroscopy has provided a way to directly couple to these far to mid-infrared excitations and study their dynamics with the ultimate time resolution – faster than a single cycle of light. However, the spatial resolution of far-field terahertz studies is intrinsically limited to the scale of the probing wavelength by diffraction. Scattering-type near-field scanning optical microscopy (s-NSOM) has the potential to overcome this limitation. Here, we demonstrate a unique combination of ultrafast terahertz spectroscopy with s-NSOM. Phase-stable mid-infrared pulses are scattered off the tip of an atomic force microscope and detected by electro-optic sampling, enabling the observation of the oscillating electric near-field with 10-nm spatial resolution and 10-fs temporal resolution. We apply our novel microscope to study the ultrafast local carrier dynamics in an indium arsenide nanowire. By resolving the oscillating scattered near-field as a function of pump-probe delay time and position, we record an ultrafast movie of the local evolution of the electron density with sub-cycle time resolution. The development of field-sensitive spectroscopy with sub-nanoparticle spatial resolution marks the dawn of a new era for sub-cycle measurements, where nanoscale experiments can be envisioned for virtually any process suitable for time-resolved studies in the mid-infrared.

Biography:

Dr Shashi Paul is working in the Emerging Technologies Research Centre (EMTERC), De Montfort University, and Leicester, United Kingdom, as a reader in Nanoscience and Nanotechnology and head of EMTERC (http://www.dmu.ac.uk/emterc). He graduated from Indian Institute of Science (IISc), Bangalore and previously worked at Cambridge University, Durham University and Rutgers University. He has extensive experience in the field of deposition of nano-sized organic and inorganic materials in the context of their applications to electronic memory devices, thin film transistors, biological & chemical sensors and energy related devices.

Abstract:

Silicon is widely used in electronic industries in a number of forms, for example: amorphous silicon is used in liquid-crystal display units; poly-silicon is used in Flash memory structures & photovoltaic solar cells and single crystals are used in C-MOS technologies. Among various forms of silicon embodiments, silicon nano-structures (for example silicon nanowires). However, before silicon nano-structures become integrated into a commercial product (for example in consumer plastic electronics or batteries), there are still major challenges to conquer. These include optimizing growth conditions, low-temperature growth of silicon nano-structures. For the growth of nano-structures, widely employed chemical vapour deposition (CVD) techniques is in practice. However, the growth temperatures relevant to this technique exceed 600oC, which results in very high thermal budgets and process is not compatible cheap and flexible substrates. Using a combination of pre-growth preparation steps and plasma enhanced chemical vapour deposition (PECVD), (UK patent #GB2482915), have been shown to result in the growth of silicon structures (micro and nano sized) ï‚£ 300ï‚°C. Using this process, we are able to grow silicon structures on plastic/glass substrates and have demonstrated their use in electronic and energy related devices.

Biography:

Tamara Milivojević has completed her Ph.D in December 2014, from the University of Ljubljana, Slovenia. Her prime focus was the effect of ZnO nanoparticles on different levels of biological organization. She is the author and co-author of several papers in reputed journals. She presented her work as a speaker at the international conferences and symposiums. Beside bionanotechnology, she studies the biology and taxonomy of Hymenoptera.

Abstract:

The increase in the production of nanomaterials in the past decades introduced both positive and negative prospects in the consumer goods. ZnO nanoparticles are amongst the most frequently used and globally produced nanomaterials. Oral ingestion is one of the already acknowledged exposure routes for the unintentional consumption of ZnO nanoparticles with negative implications. Our goal was to study the effects of chronic dietary exposure to ZnO nanoparticles on chosen cardiac parameters. For this purpose Wistar rats were treated daily with oral doses of 4.76 and 47.60 mg ZnO nanoparticles/kg of body weight during chronic six week exposure. Although the isolated heart model was previously used to study nanoparticle effect on cardiac parameters, this is the first use of the isolated heart model for the study of negative effects of ZnO nanoparticles. We studied cardiac function in terms of ventricle developed pressure, heart rate, coronary flow and the presence of arrhythmia. Our data shows that the chronic consumption of ZnO nanoparticles induces dose-dependent cardiotoxic effect on Wistar rats. We observed impaired cardiac function in terms of decreased left ventricle developed pressure and coronary flow, and the generation of ventricular tachycardia. In the absence of similar studies, this is the first evidence of direct negative implications of the chronic oral ingestion of ZnO nanoparticles on the heart function. The present study introduces new views on previous knowledge regarding lowest observed effect concentration in terms of the chronic dietary exposure to ZnO nanoparticles.

Biography:

I’m now a lecturer of Genetics inZoology Department Faculty of Science Cairo University, obtaining the M.Sc (2008) and ph.D degrees (2012) in Cyto and Molecular Genetics from Faculty of Science Cairo University. Now, teaching various courses in Faculty of Science Cairo University and has good experience in various techniques including Comet, micronucleus and chromosomal aberrations analysis assays and single strand conformational polymorohism (SSCP) ......etc. Attending several conferences and workshops and sharing in the Institutional Animal Care and Use Committee (IACUC) of the Faculty of Science of Cairo University since 2012 Interests: I have interests in several scientific branches including: Genetics, Molecular biology, Comet assay, Nanotoxicology, Safety evaluation and cancer research.

Abstract:

Nanoparticles are widely used in a wide variety of applications due to their high stability, resistance, and photocatalytic properties. Titanium dioxide (TiO2) nanoparticles are commercially used in a variety of consumer products e.g., toothpastes, sunscreens, cosmetics, food products, medications and wastewater treatment, that increasing daily human exposure to them. Therefore, TiO2 nanoparticles persistence and its effect on cancer incidence were investigated in this study. Significant elevations in tail length, %DNA damage and tail moment by nano-TiO2 particles during the experimental period evidenced the persistence of DNA damage. This was further confirmed by the appearance of laddered fragmentized and smeared genomic DNA. Moreover, the incidence in p53 mutations was increased by increasing the experimental period in nano-TiO2 treated groups. All these could be attributed to the persisted titanium accumulation and no clearance with time. Conclusion: persisted accumulation and no clearance of nano-titanium after stopping exposure enhanced its toxicity and increases the incidence of cancer.

Biography:

Dr. AmanUllah received his PhD (with distinction) in Chemical Sciences and Technologies in 2010 at the University of Genova, Italy by working together at Southern Methodist University, USA. He is currently working as an Assistant Professor at the Department of Agricultural, Food and Nutritional Science, University of Alberta. He has published more than 20 papers in reputed journals.Amanwas named a Canadian Rising Star in Global Health by Grand Challenges Canada in 2012.

Abstract:

Amphiphilic block copolymers and ABA type PEG-Lipid conjugated macromolecules have been synthesized using microwave-assisted reversible addition-fragmentation chain transfer (RAFT) polymerization and the copper-catalyzed azide-alkyne cycloaddition commonly termed as “click chemistry” respectively. Characterization of the block copolymers and conjugates has been carried out with the help of 1H-NMR, FTIR and GPC. These copolymers and conjugates were evaluated for the encapsulation and release of drug. Carbamazepine, an anticonvulsant drug with poor water solubility was selected to be a hydrophobic drug model in the study. Themicellization, drug encapsulation and release behavior of macromolecules was investigated by dynamic light scattering (DLS), transmission electron microscope (TEM) and fluorescence spectroscopy. From the results, it has been concluded that the nanoparticles had different average sizes due to different ratio of hydrophilic contents in the block or conjugate backbone. The particle size and structure could be altered by changing the ratio of hydrophilic and hydrophobic contents. The in vitro drug encapsulations highlighted that all the drug-loaded micelles had spherical or near-spherical morphology. In vitro drug release study showed the controlled release of hydrophobic drug over a period of max. 50 hours. The results indicate that there is great potential of renewable lipid-based micelle nanoparticles to be used as hydrophobic drug carriers.

Biography:

Abstract:

In this paper, the resonant frequency of a T-shaped nano-antenna was analysed and parametric study had been carried out to understand the effects on T-shaped antenna on diamond like carbon material. The novel T-shaped nano-antenna were designed and analysed by using momentum model in Advanced Design System (ADS) software and the simulations results were directly compared with other nano-antenna. Initial work indicated that the novel T-shaped nano-antenna had a smaller physical size and higher bandwidth when compared to the other nano-antenna at milli-metric wave frequencies.