Scientific Program

Conference Series Ltd invites all the participants across the globe to attend 4th International Conference on Condensed Matter and Materials Physics London, UK

Venue: Park Inn by Radisson Hotel & Conference Centre London Heathrow.

Day 1 :

Keynote Forum

Subhendra Dev Mahanti

Michigan State University, USA

Keynote: Recent advances and challenges in thermoelectrics

Time : 09:30-10:15

Conference Series Materials Physics 2018 International Conference Keynote Speaker Subhendra Dev Mahanti photo
Biography:

Subhendra Dev Mahanti obtained his BSc from Utkal University in 1961; MSc from Allahabad University in 1963; PhD in Theoretical Condensed Matter Physics from the University of California, Riverside (USA) in 1968. After two years at Bell Telephone Laboratories, he joined Michigan State University in 1970, where he has been a Full Professor since 1982 and is currently an Emeritus Professor. His research is in the area of magnetism, high Tc superconductors, multi-ferroics, physical systems showing colossal magnetic resistance, thermoelectrics, and topological insulators. He has published nearly 300 papers in reputed journals.

Abstract:

Global energy issues have created a pressure to increase both the use of renewable sources of energy and the efficiency of current power generation and utilization. In the latter context thermoelectricity can play an important role in addressing the problems of energy utilization and management. The major challenge facing the thermoelectric research is to improve the efficiency which depends on dimensionless figure of merit (is thermopower,  is electrical conductivity, is total thermal conductivity usually dominated by the phonons and  is the operating temperature). To achieve higher efficiency, ideas like quantum confinement, electron crystal phonon glass, nanostructuring, hierarchical structures, energy filtering, low-dimensional charge transport created by highly anisotropic electronic band structure, etc. have impacted the field of thermoelectrics during the last several decades. In this talk I will review some of the recent advances in the field and discuss how ab initio theoretical calculations are contributing to and clarifying these ideas. Some of the systems I will discuss are (i) thermoelectric materials with intrinsically low thermal conductivity such as layered SnSe and bulk systems with effective superlattice structure Bi(CuSe)O and Sr(AgSe)F where CuSe(AgSe) layers are sandwiched between Bi-O (Sr-F) layers; (ii) 3-dimensional systems with highly anisotropic electronic bands as in Heusler systems. I will also briefly discuss recent work on computationally guided discovery of novel thermoelelctric materials for example, n-type Zintl compounds.

 

Keynote Forum

Sang Yeol Lee

Cheongju University, Republic of South Korea

Keynote: Thin film circuits with amorphous oxide thin film transistor

Time : 10:15-11:00

Conference Series Materials Physics 2018 International Conference Keynote Speaker Sang Yeol Lee photo
Biography:

Sang Yeol Lee obtained his BS Degree in the Department of Electrical Engineering at Yonsei University (Republic of South Korea) in 1986; MS and PhD Degrees in the Department of Electrical and Computer Engineering from State University of New York at Buffalo (USA) in 1990 and 1992, respectively. He has been a Full Professor in the Department of Semiconductor Engineering at the Cheongju University; Full Professor and Director of Research Institute of Advanced Semiconductor Convergence Technology. He was invited as a Visiting Scholar in Electronic Device Team, Los Alamos National Lab (USA) in 2002–2003. His research areas are ZnO electronics including oxide TFTs, LEDs, transparent conducting oxides, semiconductor processing, nanoelectronics, memory devices and displays. He is mainly interested in Materials Science.

Abstract:

Amorphous oxide thin film transistors (AOTFT) have been fabricated by RF (Radio Frequency) magnetron sputtering with the bottom gate structure. AOTFTs exhibited to change stability under the bias and temperature stress and electrical properties strongly depending on Si ratio, mainly because Si atom can act as a good carrier suppressor. Therefore, the threshold voltage (Vth) of AOTFTs could be easily controlled by changing the Si ratio. Depletion load inverter model has been consisted by using only n-type AOTFTs. This inverter model is operated by difference of Vth between depletion mode (D-mode) and enhancement mode (E-mode) controlled by Si ratio. Furthermore, the conventional NMOS logic circuit models was adopted for the realization of AOTFT-based logic circuits such as NAND, NOR and ELSE. The proposed logic circuit composed by only n-type AOTFTs could be promising in terms of high performance and simply controllable thin film type for next generation integrated circuit applications.

  • Materials Physics | Theoretical and Computational Materials Physics | Magnetic Materials and Optical Materials | Semiconductor Materials
Location: Bleriot
Speaker

Chair

Subhendra Dev Mahanti

Michigan State University, USA

Speaker

Co-Chair

Haihan Luo

Shanghai Institute of Technical Physics CAS, P R China

Session Introduction

Haihan Luo

Shanghai Institute of Technical Physics – CAS, P R China

Title: Study on the infrared optical properties and the microstructure of cesium iodide thin film
Speaker
Biography:

Haihan Luo obtained his BS Degree in Physics Department from Nanjing University in 2006 and his PhD Degree in Physical Electronics from University of Chinese Academy of Sciences in 2012 (China) respectively. He is currently working in the Department of Optical Coatings and Materials at the Shanghai Institute of Technical Physics of the Chinese Academy of Sciences. His research interests are focused on micro-nano integrated optical devices, far infrared optical interference filters design and manufacturing and optical properties analysis of thin film materials.

Abstract:

The infrared optical properties and the microstructure of cesium iodide (CSI) thin film have been investigated. In this paper, the cesium iodide thin film were prepared on CVD (chemical vapour deposition) diamond substrate by molybdenum boat thermal evaporation in 2×10-3 Pa vacuum pressure, while deposition rate was monitored and demonstrated at 2~3 nm/s by quartz crystal oscillation controller. The films were observed and analyzed by the Fourier transform infrared spectrometer, X-ray diffraction analyzer and scanning electron microscopy. CSI film infrared spectra transmittance curve shows that the cesium iodide transparent area can be up to 80 micron which is the far infrared region. When affected by the moist air, the spectral curve shows the appearance of the infrared absorption band in the ranges of 2.66~2.85 μm. XRD results indicate the cesium iodide film is polycrystalline. And the scanning electron microscopy results shows that the average grain size of the cesium iodide film become larger after the cesium iodide film is placed in the moist air.

Loik Gence

Pontifical Catholic University of Chile, Chile

Title: Micro texturing TiN and Ag coating for flexible and transparent electronics
Speaker
Biography:

Loïk Gence is received his Ph.D. from Catholic University of Louvain, Belgiuma and he is presently Assistant Professor in Instituto de Física of Pontificia Universidad Catolica de Chile, Chile.

Abstract:

Since a few years, the semiconductor industry is looking for answering to the growing demand for new electronic devices with the ability to be (inter-) connected for sharing informations with people and other devices within the framework of the so-called Internet of Everything (IoE). This demand will explode in the next few years, and will require the development of new materials and technologies that are lighter, flexible, low-power and that can be integrated in wearable devices, sensors, displays and actuators. Polymer substrates, were recently proposed as a potential candidates for light-weight, flexible and greener electronic devices. Here we studied the fabrication of conductive nanocellulose (nanopaper) substrates for flexible solar cell and electronic devices applications. Sputtered titanium nitride (TiN) were deposited onto nanopaper substrates using radio frequency capacitively coupled plasma (RFCCP). Their electrical and optical properties were scrutinized as a function of substrate synthesis and TiN deposition parameters. Micro-texturing of the TiN coating is proposed for optimizing their electro-optical properties. The electrical and optical TiN properties were compared with commercially available PET/ITO substrates and Ag Nanowires (NWs) coatings already proposed as electrodes for nanopaper-based electronics. Moreover, the conductivities of ITO, Ag NWs and TiN electrodes were scrutinized under repetitive mechanical stress, using a bending machine.

Speaker
Biography:

Mohamed El Hafidi is Professor of Quantum Physics and Magnetism at Hassan University II of Casablanca (Morocco) since 1985. He prepared a part of his PhD at the High Magnetic Field Laboratory (Grenoble, France) and he stayed as a visiting professor at Joseph Fourier University of Grenoble. He currently supervises research on topological structures and low dimensionality magnetic systems.

Abstract:

The emergence of topological structures, such as magnetic skyrmions and vortices gave a great push in memories construction. In this work, we investigate skyrmions nucleation and annihilation, and their stabilization in an amorphous ferromagnetic Co0.400Fe0.40B0.20/Pt(1.3nm) nanodisk (Fig.1.). This kind of nanomaterials are characterized by their strong perpendicular magnetic anisotropy PMA and high interface Dzyaloshinskii-Moriya interaction iDMI values (0 < D <0.45 mJ/m2) depending on the platinum layer thickness providing ideal conditions   for skyrmions birth. Notice that skyrmions are promising for ultracompact data storage processing and may open up emerging field of potential applications. This study is accomplished within the framework of a phenomenological continuum model established to characterize the chiral states in the system. Simulations are carried out using Mumax3 software. We show that iDMI favors the appearance of skyrmions in a limited range. We also elucidate the effect of a magnetic field applied perpendicularly to the plane of the nanodisk as well as the diameter of the nanodisk on the skyrmions stabilization.

Speaker
Biography:

Kazuya Masu obtained his BE, ME and PhD Degrees in Electronics Engineering from Tokyo Institute of Technology (Tokyo Tech), Japan. He was an Assistant Professor and an Associate Professor with Tohoku University from 1982. In 2000, he moved to Tokyo Tech. He is currently a Professor and Director General of Institute of Innovative Research at the same university. He was a Visiting Professor in Georgia Institute of Technology in 2002 and 2005 respectively. He received IEICE Electronics Society Award in 2004, IEICE Achievement Award in 2013 and IEEJ Outstanding Achievement Award in 2014. He served as Vice President of JSAP in 2014-2015. He is JSAP Fellow, IEEJ Fellow, and IEICE Fellow.

Abstract:

This paper presents our recent progress of a high sensitivity complementary metal-oxide semiconductor-microelectromechanical systems (CMOS-MEMS) accelerometer with gold proof-mass and its application in diagnosis of Parkinson’s disease. The feature of the CMOS-MEMS accelerometer is the use of gold proof-mass. High density of gold enables us to increase the sensitivity by reducing thermo-mechanical noise that is inversely proportional to the proof mass. We then show the developed CMOS-MEMS multi-physics design environment. An equivalent circuit of a MEMS accelerometer has been designed to simultaneously understand both the mechanical and the electrical behaviors. One of the potential applications of the high sensitivity accelerometer is also discussed by focusing on early-stage diagnosis of Parkinson’s disease.

Victor Baledent

University of Paris Sud, France

Title: New insight in the physics of RMn2O5 multiferroics

Time : 14:10-14:35

Speaker
Biography:

Victor Balédent obtained his PhD (Physics) in 2010 for his work on the magnetic properties of superconducting cuprates studied by neutron scattering, awarded by a prize from the French Neutron Society. During a two years Postdoc at synchrotron SOLEIL, he extend his research to various superconducting materials (pnictides, heavy fermions, cuprates) and widens his scientific thematics to metal-insulating transitions and multiferroicity. He is currently an Associate Professor at the University of Paris Sud, Orsay, France. He was recruited as an Assistant Professor in 2013 at the Laboratory of Solid Physics, Orsay, France. His research focus on the manifestation of electronic correlations in physical properties in several classes of material from Mott-insulators and superconductivity through multiferroics. Techniques used are neutron and X-ray elastic and inelastic scattering with different sample environment : high pressure, magnetic field and low temperature.

Abstract:

RMn2O5 materials have long been presented as spin induced multiferroic family, where the electric polarization develops concomitantly with a magnetic transition at low temperature. The complex magnetic order originates from the frustration of anti-ferromagnetic loops of 5 sites in the (a,b) plane as illustrated in the Figure. What makes them particularly interesting lies in their singular properties: an electric polarization among the strongest reported so far (3600µC.cm-2 in GdMn2O5), a strong magneto-electric coupling (enabling a polarization flip under a magnetic field of 2T in TbMn2O5), and a magnetism that indicates a different fundamental mechanism than the standard Dzyaloshinskii-Moriya Interaction. In this presentation, I will present our recent results on both atomic and magnetic structures of several members of this family, shedding a new light on the physic and problematic of RMn2O5.

Speaker
Biography:

Edgar Núñez Rojas has received Degree in Chemical Engineering, UNAM School of Chemistry, Master of Science in Materials Engineering, UNAM Materials Research Institute, Doctorate in Materials Science and Engineering, Materials Research Institute UNAM, two years of postdoctoral stay at the UAM-Iztapalapa , eleven years as a subject teacher at the Faculty of Chemistry, UNAM. Two quarters as a tenured professor level C at the UAM-Iztapalapa. He currently works at the UAM-Iztapalapa as the CONACyT Chair in the Chemistry Department.

Abstract:

Physical properties of a molecular system are function of the interaction among molecules and atoms which form such system. These interactions are divided in two kinds, intramolecular and intermolecular. Intramolecular interactions describe the energetic contribution due to the interactions within the molecular structure, namely, bonds, angle bonds and torsions mainly; functions used for these interactions are harmonic potentials- a special mathematical models for the dihedral angle. Intermolecular potentials describe the energetic contribution of the interaction between atoms which belong to different molecules in a system, they are modeled with Lennard-Jones and Coulombic potential. In molecular simulations, the force field is essential. It is a mathematical function which includes all the energetic contributions mentioned above. Also, the force field is the set of parameters required for all the terms of the mentioned function (force constants for the harmonic, constants for the functions of the torsions, equilibrium distances and angles, Lennard-Jones parameters and electrical charges, etc.). Understanding the force field and its development has allowed the description, with some limitations, of the physical behavior of molecular systems and therefore, giving a predictive character to this methodology.

Speaker
Biography:

Sergei V Aliukov has been doing his scientific research in different areas of his activity, namely, in Engineering, Materials Science, Mathematics, and others. He has published 3 monographs and more than 100 papers. He has developed new methods of approximation of generalized and piece-wise functions and some physical and mathematical models of dynamical processes.

Abstract:

At present, there is a tendency to replace metals with nonmetals, including composite materials. More and more works are devoted to the creation and investigation of the structure and properties of high-temperature nonmetallic materials. Composites, being a heterogeneous anisotropic or quasi-isotropic system, combining the positive properties of components and possessing a complex of new properties not inherent in any of them, allow to substantially improve the basic characteristics of materials. The main requirement applied to the inlet housing of gas turbine engines made of polymer composite materials is the ability to withstand a high operating temperature. Modern polymer composite materials consist of reinforcing fillers and a polymer matrix. Reinforcing fillers can be made of: fiberglass, organic fiber, carbon fiber and are able to withstand the required operating temperature with ease. Thus, the task of selecting polymer composite materials for an input device is reduced to the selection of a polymer matrix connecting the reinforcing filler. This article analyzes the use of polymer composite materials in the details of gas turbine engines of aircrafts, the most promising components of polymer composite materials for manufacturing the input case of a helicopter gas turbine engine have been selected. Samples were made and mechanical tests of polymer composite materials were carried out. Based on the results of the research, the choice of the most promising polymeric composite material was made. The experimental studies carried out on the two most promising materials showed the advantages of a material that has a significantly larger temperature range of operation and has a large margin for modification. It is shown that heat-resistant materials with short-fiber filler can be a worthy replacement for aluminum alloy in the design of the input device.

Speaker
Biography:

Golikova T E obtained her PhD Degree in Physics in 2014 and she is working on experimental investigation of the interplay of superconductivity and magnetism at low temperatures involving structure fabrication with the nanotechnology tools. Her research interest include: superconductivity and magnetism, spintronics, Josephson junctions.

Abstract:

Mesoscopic hybrid planar Josephson junctions have attracted a lot of interest in the recent decade in terms of their possible applications in the electronics, spintronics, quantum computing and fundamental research. We have investigated the transport properties of Josephson junctions based on superconductor – normal metal/ ferromagnet – superconductor (Al-Cu/Fe-Al) with double layered N/F weak link (Cu/Fe) under the controllable spin polarized current injection at low temperatures and in weak magnetic fields. Spin polarized current was injected in the middle of the Josephson junction from the perpendicular ferromagnet electrode. We have observed the supercurrent in this type of junctions show nonlinear dependence of low values injection current from F-electrode. We claimed that this effect is due to 0-p transition, i.e. the fundamental Josephson relation can be changed from I=Icsinf to I=Icsin (f+p) by controlling not only energy distribution as it was done in but also with the presence of spin polarization of the injection current. Our experiments also demonstrated the appearance of double-peak peculiarity in differential resistance at high values of the injection current which is assumed to be due to the double proximity effect.

Speaker
Biography:

Pushan Ayyub is a Senior Professor and Chair in the Department of Condensed Matter Physics at the Tata Institute of Fundamental Research, Mumbai, India. He has over 160 publications in the general area of nanoscience. He was a Member of the International Committee on Nanostructured Materials (1998-2008) and is currently a Member of the Nano Mission Council of the Government of India. He is a Fellow of the Indian National Science Academy. His research interests include the size dependence of superconductivity and ferroelectricity. He is particularly interested in size-induced structural phase transitions and stabilization of novel crystal structures.

Abstract:

The study of superconductivity in nanostructured systems is particularly fascinating due to the existence of a multitude of length scales, such as the coherence length (x) and the penetration depth (lL). Here, we focus on quasi-zero dimensional superconductors, such as isolated nanoparticles or nanocrystalline solids. In such systems, superconductivity usually persists down to length scales much smaller than x and lL. Ultimately, the lower size limit for superconducting order to exist is set by the ‘Anderson criterion’, which arises from quantum confinement and is believed to be remarkably accurate and universal. We report, however, a recent result that questions the validity of the Anderson criterion. We show that phase-pure, nanocrystalline bcc-Ta remains superconducting (with, TC»0.9K) down to sizes 40% below the conventional estimate of the Anderson limit for Ta (4.0nm). Further, both the TC and HC exhibit unusual, non-monotonic size dependences, which we explain in terms of a complex interplay of quantum size effects, surface phonon softening and lattice expansion. An estimation of TC within first-principles density functional theory shows that even a moderate lattice expansion allows superconductivity in Ta to persist down to sizes much below the Anderson limit. This indicates the possibility of bypassing the Anderson criterion by suitable crystal engineering and obtaining superconductivity at arbitrarily small sizes, an obviously exciting prospect for futuristic quantum technologies. We take a critical look at how lattice expansion modifies the Anderson limit, an issue of fundamental interest to nanoscale superconductivity.

Speaker
Biography:

Homnath Luitel is a PhD student at Variable Energy Cyclotron Centre (VECC), a research institute in Kolkata. He has done his Post MSc course from the same institute and has registered for PhD program under Homi Bhabha National Institute (HBNI), Mumbai. His research area mainly focuses on room temperature ferromagnetism in various non-magnetic semiconducting oxides; and also dilute magnetic semiconductors, defects characterization, etc.

Abstract:

Ab-initio calculations on the possibility of room temperature ferromagnetic ordering in non-magnetic oxides have been performed by doping various p-block elements X (X=B, C, N, Al, Si, P, S, Ga, Ge and As) in ZnO, TiO2, MgO, SnO2 etc. The spin-polarized density of states calculation has been performed using the code MedeA VASP for all the structures with two same p-block elements, doped at oxygen sites. A significant amount of induced magnetic moment has been observed in some cases. The sources of magnetism are np orbital electrons of the dopants along with the 2p orbital electrons of neighboring oxygen atoms. Among them, stable ferromagnetic (spin triplet) ordering states have been identified and the theoretical calculations have been verified by experiments. The room temperature ferromagnetic properties of various semiconducting oxides can be useful for spintronics applications in future. A detailed result of spin-spin interaction study along with our experimental observations for room temperature ferromagnetism in different systems will be presented.

Speaker
Biography:

Arkaprava Das is a senior research scholar in Inter University Accelerator centre, New Delhi, India and his research work focused on the development of undoped and doped cadmium oxide (CdO) thin films and their nanocomposites (NCs) for studying various phase transformation phenomenon besides the scope of their potential applications.

Abstract:

Undoped and tin doped cadmium oxide (CdO) based thin films are irradiated by 84 MeV Si6+ and 120 MeV Ag9+ ions. In the present work the charge nutrality level (CNL) in highly conducting CdO thin films is demonstarted by the observed variation in the band gap upon annealing and doping. The increase in crystallite size with tin doping is a signature of decrease of CdO stoichiometry by substitutional replacement of Cd with Sn. Each Cd2+ ions are substituted by Sn2+ ions with reduction of Sn4+ via creating oxygen vacancies in the lattice which also enhnaces the carrier concentration in the tin doped thin film. The band gap enhancement cannot be explained by Burstein Moss Shift (BMS) only but can be explained by formation of charge neutrality level (CNL). The level of local CNL resides at the branch point of virtual gap states (ViGS) generation of which is the consequence of tin doping in CdO lattice. Further investigations using soft X-ray absorption spectroscopy (SXAS) at oxygen K and cadmium M edge and the analysis of the spectral features has revealed an evidence of p-d interaction between O 2p and Cd 4d orbitals. After irradiation, the thin films exhibit an unusual band gap enhancement via generation of oxygen vacancies due to huge electronic energy deposition inside the lattice by Ag and Si ions. The observed band gap enhancement has been substantiated by a schematic block diagram.