THE PHYSICS GRADUATE PROGRAM invites everyone to the seminar:
Correlating Structural, Electronic and Ionic Diffusion Properties of Nanomaterials for Energy Storage
Profª Drª Corinne Arrouvel / UFSCar – Sorocaba
Abstract:
The quest of new materials at the nanoscale is an important topic in the modern society. The industrial interest is to improve the energy conversion, the storage capacity and the kinetic of the electrochemical energy in high-technology devices. Materials should be in addition low cost, stable under a wide range of temperature and pressure conditions and safe. This talk will introduce basic concepts of electrochemistry, of bulk and surface properties in order to explain the difference of energy carrier transport mechanisms in rechargeable lithium batteries, capacitors, solid oxide fuel cells and solar cells. Combining computational and experimental techniques, we show that some key aspects are based on the search of optimized size and morphology of their nanocomponents. Anisotropic energy pathways and crystal shape will be therefore highlighted.
Date: 05/December/2014 – (Friday) – Place: Sala 212 – Auditório do Departamento de Física- Time: 10h15min
THE PHYSICS GRADUATE PROGRAM invites everyone to the seminar:
Nonperturbative QCD effects in forward scattering at LHC
Prof. Emerson Gustavo de Souza Luna – IF/UFRGS
Abstract:
We study infrared contributions to semihard parton-parton interactions by considering an effective charge whose finite infrared behavior is constrained by a dynamical mass scale. Using an eikonal QCD-based model in order to connect this semihard parton-level dynamics to the hadron-hadron scattering, we obtain predictions for the proton-proton ($pp$) and antiproton-proton ($\bar{p}p$) total cross sections, $\sigma_{tot}^{pp,\bar{p}p}$, as well as for the ratios of the real to imaginary part of the forward scattering amplitude, $\rho^{pp,\bar{p}p}$. We discuss the theoretical aspects of this formalism and consider the phenomenological implications of a class of energy-dependent form factors in the high-energy behavior of the forward amplitude. Our results, obtained using a group of updated sets of parton distributions, are consistent with the recent data from the TOTEM experiment.
Date: 28/November/2014 – (Friday) – Place: Sala 212 – Auditório do Departamento de Física- Time: 10h15min
THE PHYSICS GRADUATE PROGRAM invites everyone to the seminar:
Aplicações de Transistores de Filme Fino em Displays Transparentes e Flexíveis
Prof. Dr. Lucas Fugikawa Santos
Universidade Estadual Paulista, UNESP, Departamento de Física – Campus de São José do Rio Preto.
Abstract:
Transistores de filme fino (TFTs) são dispositivos eletrônicos que têm sido amplamente aplicados em circuitos de controle de displays planos de matriz ativa baseados tanto em cristais líquidos (AMLCDs) quanto em diodos emissores de luz orgânicos (AMOLEDs). Embora a grande maioria dos displays de matriz ativos produzidos atualmente utilizem como material ativo o silício amorfo (a-Si), novos tipos de materiais têm sido estudados para poderem suprir as exigências de aplicações que irão requerer maiores taxas de repetição, recursos 3-D, grandes áreas, transparência e flexibilidade. Óxidos metálicos amorfos como o óxido de zinco (ZnO), óxido de zinco e índio (IZO) e óxido de índio, gálio e zinco (IGZO) são materiais que têm sido considerados como bons candidatos para substituir o a-Si em determinadas aplicações, em especial as que demandam transparência e flexibilidade. Recentemente, a produção de TFTs desses materiais depositados por solução tem chamado bastante a atenção, devido ao enorme potencial para a deposição em grandes áreas e a diminuição dos custos de produção. No presente trabalho, iremos apresentar os resultados de TFTs de óxidos metálicos processados por solução e discutir sobre os desafios tecnológicos que precisam ser superados para que esse tipo de tecnologia alcance o mercado.
[1] K.K. Banger, Y. Yamashita, K. Mori, R.L. Peterson, T. Leedham, J. Rickard and H. Sirringhaus, Nat. Mat. 10, 45-50 (2011).
[2] M.C. Gwinner, Y. Vaynzof, K.K. Banger, P.K.H. Ho, R.H. Friend and H. Sirringhaus, Adv. Funct. Mat. 20, 3457-3465 (2010)
Date: 21/November/2014 – (Friday) – Place: Sala 212 – Auditório do Departamento de Física– Time: 10h15min
THE PHYSICS GRADUATE PROGRAM invites everyone to the seminar:
Studies of Dipolar Bose-Einstein condensates in optical lattices
Prof. Dr. Emanuel Alves de Lima Henn – Instituto de Física de São Carlos / USP
Abstract:
In this talk we discuss some aspects of a strongly dipolar, Chromium Bose-Einstein condensate in an optical lattice, focusing on its stability and in the observed confinement induced-collapse of the condensate when release from the trap. Optical lattices are rich playgrounds for dipolar BECs since this environment brings into play the interplay between short and long range interactions and, if suitably tailored, make the dipolar BEC much more stable, bringing it closer to reveal some interesting and new phases predicted theoretically. In this talk we show the first measurements of the stability of a dipolar BEC in an optical lattice and also the phenomena of dipolar collapse induced by a change in the cloud geometry. We also discuss new perspectives in the field of dipolar quantum gases.
Date: 14/November/2014 – (Friday) – Place: Sala 212 – Auditório do Departamento de Física– Time: 10h15min
