The Effect of Space Charge due to the Auto-Ionization of Neutral, Hydrogenic States in Point-Contact Germanium Detectors at MilliKelvin Temperatures - new
D. Faiez, N. Mirabolfathi, B. Sadoulet, K. M. Sundqvist
Department of Physics, University of California - Berkeley, Berkeley, CA, USA
Department of Electrical & Computer Engineering, Texas A&M University, College Station, TX, USA
A class of semiconducting detectors, operated at temperature T~50mK, has direct application to the search for dark matter particle, when are able to simultaneously measure both the ionization and phonons created by particle interactions. We explore the effect of space charge accumulation in a germanium p-type point contact detector which arises due to the auto-ionization of hydrogenic ...
Modelling Ultra-short Pulse Laser Ablation of Dielectric Materials Using multiple Rate Equations - new
P. Boerner, K. Wegener
Institute of Machine Tools and Manufacturing, ETH Zurich, Zurich, Switzerland
Ultrafast lasers are widely applied in micromachining, material science and physics. In industry, picosecond lasers are becoming more and more established. For pulse lengths shorter than the electron-phonon coupling time, heat affected zones are negligible. Thermally sensitive materials can be processed using ultrashort pulse laser radiation. Multi-component materials and poorly absorbing ...
F. Bosia, P. Olivero, and E. Vittone
Dipartimento di Fisica Teorica, Università di Torino, Torino, Italy
Dipartimento di Fisica Sperimentale, Università di Torino, Torino, Italy
Ion implantation in insulating materials leads to local variations in mechanical and optical properties that can be exploited for the fabrication of micro-structures. In particular, ion irradiation of diamond causes the formation of buried amorphised layers, with correspondent mass density and refractive index variations that depend on the level of “damage” of the crystal structure. ...
Untersuchung der Polarisationseigenschaften einer mikrostrukturierten optischen Faser unter dem Einfluss äußerer Belastung
A. Unger, and K.H. Witte
 FH-Wiesbaden, Fachbereich Physikalische Technik, Rüsselsheim;
 FH-Wiesbaden, Fachbereich Elektrotechnik, Rüsselsheim
Mit Hilfe des Softwareprogramms COMSOL zur Modellierung physikalischer Vorgänge wurden die Polarisationseigenschaften einer mikrostrukturierten Singlemodefaser untersucht. Ausgangspunkt der Simulationen waren experimentelle Untersuchungen, nach denen diese Faser eine ungewöhnlich starke Doppelbrechung aufwies. Die Doppelbrechung der Faser und damit ihre Fähigkeit zur Polarisationserhaltung ...
H.-H. Yeh, Y.-F. Chau
Department of Electronic Engineering, Ching Yun University, Taiwan
High birefringence induced by complex unit cells of elliptical air holes in photonic crystal fibers (PCFs) is analyzed numerically using COMSOL Multiphysics. Two types of our proposed PCFs and a previous structure are investigated. The statistical correlations between the birefringence and the various parameters are obtained. The birefringence is found to be largely dependent on the variation of ...
C. Grau Turuelo, B. Bergmann, C. Breitkopf, F. Hoffmann, L. Brencher
Technische Universität Dresden, Dresden, Saxony, Germany
Infineon Technologies GmbH, Dresden, Dresden, Saxony, Germany
A novel technique for semiconductor manufacturing is introduced: Silicon-On-Nothing. This process consists of an initial cylindrical trench which has a shape evolution under certain conditions: high temperature (1100 °C), low pressure (10 Torr) and a non-oxidizing atmosphere such as hydrogen. These conditions enable a, mainly, surface diffusion phenomenon whose final result is an empty space ...
C. Soares, N. Padoin, A. C. Zimmermann, G. Cunha, P. B. Uliana, M. Wendhausen
Federal University of Santa Catarina, Florianópolis, SC, Brazil
PowerOpticks Technology Ltda, Florianópolis, SC, Brazil
In this study, COMSOL Multiphysics® software was applied to the investigation of the electromagnetic behavior of an optical crystal submitted to the magnetic field generated by electric current in a near positioned metallic conductor. Moreover, the influence of a ferromagnetic apparatus (magnetic concentrator) on the magnetic field acting upon the crystal was investigated. Three cases were ...
F. Beltrán-Mejía[1, 2], C. M. B. Cordeiro
Universidade Estadual de Campinas - UNICAMP, SP, Brasil
Atualmente no Instituto Nacional de Telecomunicações (INATEL), Santa Rita do Sapucaí, MG, Brasil
Uma fibra óptica retorcida pode se converter em uma estrutura longitudinalmente invariante através de uma transformação de coordenadas. O anterior permite fazer um analise de modos transversais da fibra, servindo para estudar a geração de modos com momento angular orbital (OAM). Atualmente, os modos OAM se encontram em diversas aplicações como na microscopia e nas telecomunicações entre ...
F. Banfi, D. Nardi, and M. Travagliati
Dipartimento Matematica e Fisica, Università Cattolica, Brescia, Italy
JILA, University of Colorado at Boulder, Boulder, Colorado, United States
Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa, Italy
Ultrafast optical generation of pseudosurface acoustic waves is investigated in hypersonic surface phononic crystals. The thermomechanics is modeled from first-principles to follow the initial impulsive heat-driven displacement in the time domain. Spectral decomposition of the displacement over the surface phononic crystal eigenmodes outlines asymmetric resonances featuring the coupling between ...
Determination of the Optical Properties of Individual Gold Nanorods through Numerical Modeling and Experiment
Y. Davletshin, J.C. Kumaradas
Ryerson University, Toronto, ON, Canada
The optical scattering and absorption of gold nanorods (GNRs) depends on its size, shape, and surroundings. This dependence is due to both intrinsic and extrinsic effects. A good understanding of this dependence is needed for applications of GNRs in photo-thermal therapy, optical and opto-acoustic imaging, biosensing, and other photonic areas. Extrinsic effects are caused by the production of ...