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Monday Morning, October 19, 2015
Monday Morning, October 19, 2015 Energy Frontiers Focus Topic Willow glass is a new material introduced recently to the market, while nickel is a inexpensive flexible reflective foil. The Corning Willow glass is Room: 211B - Session EN+AS+EM+NS+SE+SS+TF- coated with a molybdenum layer as a reflective back contact layer. By using MoM a single step and a solution deposition method, lower production cost are achievable. For thin film deposition, we used a non-vacuum spin coater (WS650 spin processor, Laurell Technologies) with an optimized spin coat Solar Cells I programming. Annealing took place under vacuum in a RTP furnace while Moderator: Jason Baxter, Drexel University, Chintalapalle time, temperature and ramp functions were varied. The other layers of the Ramana, University of Texas at El Paso device consists of cadmium sulfide n-type window layer and a zinc oxide doped with aluminum transparent top contact layer. Characterization and analysis of the thin films were performed using Raman spectroscopy, 8:20am EN+AS+EM+NS+SE+SS+TF-MoM1 Elevated Temperature scanning election microscope (Zeiss NEON 40), X-ray diffraction (Philipps Phase Stability of CZTS-Se Thin Films for Solar Cells, E. Chagarov, K. X’Pert), proflimeter (Veeco Dektak 150), UV-Vis-NIR Spectrophotometer Sardashti, University of California at San Diego, D.B. Mitzi, Duke (Carry 5000), Hall Effect measurement system (HMS3000) and 4 point University, R.A. Haight, IBM T.J. Watson Research Center, Andrew C. probe (Lucas Labs) measurements. Results show CZTS thin film solar cells Kummel, University of California at San Diego on flexible glass is obtainable. -
JOURNAL of CONDENSED MATTER NUCLEAR SCIENCE Experiments and Methods in Cold Fusion
JOURNAL OF CONDENSED MATTER NUCLEAR SCIENCE Experiments and Methods in Cold Fusion Proceedings of the first French Symposium RNBE-2016 on Condensed Matter Nuclear Science (Réactions Nucléaires à Basse Énergie), March 18–20, 2016 VOLUME 21, November 2016 JOURNAL OF CONDENSED MATTER NUCLEAR SCIENCE Experiments and Methods in Cold Fusion Editor-in-Chief Jean-Paul Biberian Marseille, France Editorial Board Peter Hagelstein Xing Zhong Li Edmund Storms MIT, USA Tsinghua University, China KivaLabs, LLC, USA George Miley Michael McKubre Fusion Studies Laboratory, SRI International, USA University of Illinois, USA JOURNAL OF CONDENSED MATTER NUCLEAR SCIENCE Volume 21, November 2016 © 2016 ISCMNS. All rights reserved. ISSN 2227-3123 This journal and the individual contributions contained in it are protected under copyright by ISCMNS and the following terms and conditions apply. Electronic usage or storage of data JCMNS is an open-access scientific journal and no special permissions or fees are required to download for personal non-commercial use or for teaching purposes in an educational institution. All other uses including printing, copying, distribution require the written consent of ISCMNS. Permission of the ISCMNS and payment of a fee are required for photocopying, including multiple or systematic copying, copying for advertising or promotional purposes, resale, and all forms of document delivery. Permissions may be sought directly from ISCMNS, E-mail: [email protected]. For further details you may also visit our web site: http:/www.iscmns.org/CMNS/ Members of ISCMNS may reproduce the table of contents or prepare lists of articles for internal circulation within their institutions. Orders, claims, author inquiries and journal inquiries Please contact the Editor in Chief, [email protected] or [email protected] J. -
Long Coherence Time and Precision Measurement of Atomic Interactions in a Bose-Einstein Condensate
Long Coherence Time and Precision Measurement of Atomic Interactions in a Bose-Einstein Condensate M. Egorov, V. Ivannikov, R. Anderson, I. Mordovin, B. Opanchuk, B.V. Hall, P. Drummond, P. Hannaford and A. I. Sidorov Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology, Melbourne 3122, Australia [email protected] Abstract: We report a high precision method of measuring s-wave scattering lengths in a Bose-Einstein condensate (BEC) and a coherence time of 2.8 s in a Ramsey interferometer employing an interacting BEC. 1. Introduction Atomic interactions play a major role in ultracold quantum gases, matter-wave interferometry and frequency shifts of atomic clocks. Precise knowledge of inter-particle interaction strengths is important because the dynamical evolution of a Bose-Einstein condensate is highly sensitive to atomic collisions and BEC interferometry is greatly influenced by mean-field driven dephasing [1] and quantum phase diffusion [2]. Here we demonstrate that in the presence of atomic interactions the interference contrast can be enhanced by mean-field rephasing of the condensate and the timely application of a spin echo pulse [3]. We observe a periodic decrease and revival of the contrast with a slowly decaying magnitude. We also employ collective oscillations of a two-component BEC for −4 the precision measurement of the interspecies scattering length a12 with a relative uncertainty of 1.6 × 10 . 2. Periodical Rephasing and Long Coherence Time of BEC A 87Rb condensate is trapped in a cigar-shaped magnetic trap on an atom chip [4] in two internal states (|1 = |F =1,mF = −1 and |2 = |F =2,mF =+1) coupled via a two-photon MW-RF transition. -
Research Article Nuclear Processes in Dark Interstellar Matter of H(0) Decrease the Hope of Migrating to Exoplanets
AAAS Space: Science & Technology Volume 2021, Article ID 9846852, 6 pages https://doi.org/10.34133/2021/9846852 Research Article Nuclear Processes in Dark Interstellar Matter of H(0) Decrease the Hope of Migrating to Exoplanets Leif Holmlid Department of Chemistry and Molecular Biology, University of Gothenburg, SE-412 96 Göteborg, Sweden Correspondence should be addressed to Leif Holmlid; [email protected] Received 24 November 2020; Accepted 11 August 2021; Published 3 September 2021 Copyright © 2021 Leif Holmlid. Exclusive Licensee Beijing Institute of Technology Press. Distributed under a Creative Commons Attribution License (CC BY 4.0). It is still generally assumed that interstellar travel will be possible after purely technical development and thus that mankind can move to some suitable exoplanet when needed. However, recent research indicates this not to be the case, since interstellar space is filled with enough ultradense hydrogen H(0) as stable condensed dark matter (Holmlid, Astrophysical Journal 2018) to make interstellar space travel at the required and technically feasible relativistic velocities (Holmlid et al, Acta Astronautica 2020) almost impossible. H(0) can be observed to exist in space from the so-called extended red emission (ERE) features observed in space. A recent review (Holmlid et al., Physica Scripta 2019) describes the properties of H(0). H(0) gives nuclear processes emitting kaons and other particles, with kinetic energies even above 100 MeV after induction for example by fast particle (spaceship) impact. These high particle energies give radiative temperatures of 12000 K in collisions against a solid surface and will rapidly destroy any spaceship structure moving into the H(0) clouds at relativistic velocity. -
Lattice Dynamics of the Excitonic Insulator ${\Rm Ta} 2{\Rm Ni}({\Rm Se} {1-X}{\Rm S} X) 5$
PHYSICAL REVIEW B 104, 045102 (2021) Editors’ Suggestion Lattice dynamics of the excitonic insulator Ta2Ni(Se1−xSx)5 Mai Ye ,1,* Pavel A. Volkov ,1,† Himanshu Lohani,2 Irena Feldman,2 Minsung Kim,1 Amit Kanigel,2 and Girsh Blumberg 1,3,‡ 1Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA 2Department of Physics, Technion–Israel Institute of Technology, Haifa 32000, Israel 3National Institute of Chemical Physics and Biophysics, 12618 Tallinn, Estonia (Received 22 April 2021; accepted 9 June 2021; published 2 July 2021) Recently, we employed electronic polarization-resolved Raman spectroscopy to reveal the strongly correlated excitonic insulator (EI) nature of Ta2NiSe5 [Volkov et al., npj Quant. Mater. 6, 52 (2021)], and also showed that for Ta2Ni(Se1−xSx )5 alloys the critical excitonic fluctuations diminish with sulfur concentration x, exposing a cooperating lattice instability that takes over for large x [Volkov et al., arXiv:2104.07032]. Here we focus on the lattice dynamics of the EI family Ta2Ni(Se1−xSx )5 (x = 0,..., 1). We identify all Raman-active optical phonons of Ag (fully symmetric) and B2g (ac-quadrupole-like) symmetries (D2h point group) and study their evolution with temperature and sulfur concentration. We demonstrate the change of selection rules at temperatures below the orthorhombic-to-monoclinic transition at Tc (x) that is related to the EI phase. We find that Tc (x) decrease monotonically from 328 K for Ta2NiSe5 to 120 K for Ta2NiS5 and that the magnitude of lattice distortion also de- creases with the sulfur concentration x.Forx < 0.7, the two lowest frequency B2g phonon modes show strongly asymmetric line shapes at high temperatures due to Fano interference with the broad excitonic continuum present in a semimetallic state. -
GOTHIC Michelucci Alessandro All Is Light Intelligent Design GOTHIC - All Is Light - Intelligent Design
GOTHIC Michelucci Alessandro All is Light Intelligent Design GOTHIC GOTHIC - All is light - intelligent design - intelligent - All is light Alessandro Michelucci EOTI This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License. To view a copy of this license, visit http://creativecom- mons.org/licenses/by-sa/3.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA Publication: EOTI Composition and typesetting: EOTI Published in Berlin - Germany ISBN 978-3-00-061246-6 EOTI - European Organization of Translators and Interpreters® Internet presence: www.eoti.eu e-mail: [email protected] EOTI - Heidenfeldstraße 8 10249 - Berlin “The reasons for using the Garamond typefaces rather than Gothic typefaces do not lie in the Antiqua-Fraktur dispute, but rather in the desire to recall the French Renaissance form.” “Sigillum burgensium de berlin sum” (Ich bin das Siegel der Bürger von Berlin) GOTHIC All is Light Intelligent Design Written by Alessandro Michelucci EOTI vi INDEX PREFACE ............................................................................................................ viii I. LIGHT AS “THEOLOGICAL SYMBOL”.................................................................. 1 II. LIGHT AS “CONCEPT OF MERE VISION”........................................................ 13 III. ALL IS LIGHT ............................................................................................... 24 IV. A NEW POLITICAL VISION ........................................................................... -
States of Matter Project Pdf
States of matter project pdf Continue Do not be confused with phase (matter). Different forms that differ in terms of the four general states of matter. From top left are solid, liquid, plasma and gas represented by the ice sculpture, a drop of water, electric arc arcs from the Tesla coil and the air around the clouds. In physics, the state of matter is one of the different forms in which matter may exist. Four states of matter are observable in everyday life: solid, liquid, gas and plasma. It is known that there are many intermediate states, such as liquid crystal, and some countries exist only in extreme conditions, such as Bose-Einstein condensates, neutron-degenerate and plasma quark-glucon, which occur only in situations of extreme cold, extreme density and extremely high energy. For a complete list of all exotic states of matter, see the list of states of matter. In the past, the distinction was made on the basis of qualitative differences in properties. Solid matter maintains a fixed volume and shape, with composite particles (atoms, molecules or ions) close to each other and fixed in place. The fabric in a state of liquid supports a fixed volume, but has a variable shape that adapts to its container. Its particles are still close to each other, but they move freely. The matter in the gaseous state has both variable volume and shape, adapting both to fit in the container. Its particles are neither close to each other nor fixed in place. Matter in the state of plasma has variable volume and shape, and contains neutral atoms, as well as a significant number of ions and electrons, both of which can move freely. -
Photoinduced Multistage Phase Transitions in Ta2nise5
Photoinduced multistage phase transitions in Ta2NiSe5 ‡ 1 ‡ 1,2 ‡ 3 1 1 1 Q. M. Liu , D.Wu ∗ , Z. A. Li , L. Y. Shi, Z. X. Wang, S. J. Zhang, 1 1 3 3 1 1, 4 T. Lin, T. C. Hu, H. F. Tian, J. Q. Li, T. Dong, and N. L. Wang∗ 1 International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China 2 Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China 3 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China 4 Collaborative Innovation Center of Quantum Matter, Beijing, China Abstract: Utrafast control of material physical properties represents a rapid developing field in con- densed matter physics. Yet, accessing to the long-lived photoinduced electronic states is still in its early stage, especially with respect to an insulator to metal phase transition. Here, by combing transport mea- surement with ultrashort photoexcitation and coherent phonon spectroscopy, we report on photoinduced multistage phase transitions in Ta2NiSe5. Upon excitation by weak pulse intensity, the system is triggered to a short-lived state accompanied by a structural change. Further increasing the excitation intensity beyond a threshold, a photoinduced steady new state is achieved where the resistivity drops by more than four orders at temperature 50 K. This new state is thermally stable up to at least 350 K and exhibits the lattice structure different from any of the thermally accessible equilibrium states. Transmission electron microscopy reveals an in-chain Ta atom displacement in the photoinduced new structure phase. We also found that nano-sheet samples with the thickness less than the optical penetration depth are required for attaining a complete transition. -
Redshifts in Space Caused by Stimulated Raman Scattering in Cold Intergalactic Rydberg Matter with Experimental Verification¦ L
Journal of Experimental and Theoretical Physics, Vol. 100, No. 4, 2005, pp. 637–644. From Zhurnal Éksperimental’noÏ i TeoreticheskoÏ Fiziki, Vol. 127, No. 4, 2005, pp. 723–731. Original English Text Copyright © 2005 by Holmlid. NUCLEI, PARTICLES, FIELDS, GRAVITATION, AND ASTROPHYSICS Redshifts in Space Caused by Stimulated Raman Scattering in Cold Intergalactic Rydberg Matter with Experimental Verification¶ L. Holmlid Atmospheric Science, Department of Chemistry, Göteborg University, SE-412 96 Göteborg, Sweden e-mail: [email protected] Received September 23, 2004 Abstract—The quantized redshifts observed from galaxies in the local supercluster have recently been shown to be well described by stimulated Stokes Raman processes in intergalactic Rydberg matter (RM). The size of the quanta corresponds to transitions in the planar clusters forming the RM, of the order of 6 × 10–6 cm–1. A stimulated Stokes Raman process gives redshifts that are independent of the wavelength of the radiation, and it allows the radiation to proceed without deflection, in agreement with observation. Such redshifts must also be additive during the passage through space. Rydberg matter is common in space and explains the observed Fara- day rotation in intergalactic space and the spectroscopic signatures called unidentified infrared bands (UIBs) and diffuse interstellar bands (DIBs). Rydberg matter was also recently proposed to be baryonic dark matter. Experi- ments now show directly that IR light is redshifted by a Stokes stimulated Raman process in cold RM. Shifts of 0.02 cm–1 are regularly observed. It is shown by detailed calculations based on the experimental results that the redshifts due to Stokes scattering are of at least the same magnitude as observations. -
Impurity Recombination of Rydberg Matter E
Impurity recombination of Rydberg matter E. A. Manykin, M. I. Ozhovan, and P. P. Polu6ktov Russian Scientific Center "Kurchatov Institute," 123182 Moscow, Russia (Submitted 25 June 1993) Zh. Eksp. Teor. Fiz. 105, 50-61 (January 1994) We consider the trapping of electrons by electronegative impurities from the conduction band for condensed systems of highly excited atoms (Rydberg matter). The trapping can occur both with photon emission and through a nonradiative mechanism. In both cases the transition of electrons from the conduction band of the condensate to impurity orbitals is possible in practice only in the regions where the electron motion is classically admissible. We show that the rate of radiative processes increases with an increase in the quantum- mechanical level of excitation of the atoms, whereas the rate of the nonradiative processes decreases rapidly. When the impurity density is comparable to the skeleton density of the Rydberg matter, the trapping of electrons by impurities leads to a fast decay of the condensate. At the same time, for low densities of the impurities, after electron trapping they will be incorporated into the structure of the Rydberg matter; as a result, the recombination of excitations is improbable. 1. INTRODUCTION equilibrium parameters of RM in the framework of a den- sity functional theory using the concept of the pseudopo- One can invoke condensed excited states (CES) to de- tential of excited atoms from which the CES is formed.' scribe dense systems of excited centers (atoms, molecules, For definiteness, we give briefly the numerical parameters impurities in solids).'.' The well known electron-hole of RM formed as the result of the condensation of cesium state, which occurs as the result of the condensation of atoms excited in an s state. -
Download Ultrasonic Spectroscopy Applications in Condensed Matter
ULTRASONIC SPECTROSCOPY APPLICATIONS IN CONDENSED MATTER PHYSICS AND MATERIALS SCIENCE 1ST EDITION DOWNLOAD FREE BOOK Robert G Leisure | --- | --- | --- | 9781107154131 | --- | --- Condensed matter physics Built by scientists, for scientists. My research interests are motivated by this remarkable observation. One example is the incorporation of multiple functionalities such as superconductivity, magnetism, and ferroelectricity into a single material platform in search of multifunctionality. Cold atoms in optical lattices are used as quantum simulatorsthat is, they act as controllable systems that can model behavior of more complicated systems, such as frustrated magnets. One major project involves studies of ultrathin dielectrics silicon oxynitrides and metaloxides for nanoelectronic devices. Optical absorption and fluorescence spectroscopy measurements have become an important tool for structure-based characterization and DNA- assisted manipulation of carbon nanotubes. Other vigorous areas of research include such phenomena as metal-insulator transition, two- dimensional electron systems, magnetism, and quantum fluids and solids. In these systems, density currents propagating in chiral edge states are protected from scattering with disorder, which is a clear advantage for exciton based optical circuits. Branch of physics. Introduction to Many Body Physics. We can also create novel multiferroic, superconducting or ferroelectric materials by means of atomic-scale crystal-symmetry engineering. The methods are suitable to study defects, diffusion, -
Coulombic Phase Transitions in Dense Plasmas
Coulombic Phase Transitions in Dense Plasmas∗ W. Ebeling1, G. Norman2 1 Institut f¨ur Physik, Humboldt-Universit¨at Berlin, Invalidenstrasse 110, D-10115 Berlin, Germany; [email protected] 2 Institute for High Energy Densities, AIHT of RAS, Izhorskaya street 13/19, Moscow 125412, Russia; henry [email protected] We give a survey on the predictions of Coulombic phase transitions in dense plasmas (PPT) and derive several new results on the properties of these transitions. In particular we discuss several types of the critical point and the spinodal curves of quantum Coulombic systems. We construct a simple theoretical model which shows (in dependence on the parameter values) either one alkali- type transition (Coulombic and van der Waals forces determine the critical point) or one Coulombic transition and another van der Waals transition. We investigate the conditions to find separate Van der Waals and Coulomb transitions in one system (typical for hydrogen and noble gas-type plasmas). The separated Coulombic transitions which are strongly influenced by quantum effects are the hypothetical PPT, they are in full analogy to the known Coulombic transitions in classical ionic systems. Finally we give a discussion of several numerical and experimental results referring to the PPT in high pressure plasmas. I. FIRST ORDER VAN DER WAALS AND range repulsion. We remember that the two phases in COULOMB TRANSITIONS the van der Waals model differ from each other by the density of molecules. The two phases in PPT have dif- ferent number densities of charged particles and different The theory of gases developed in the dissertation of degrees of ionization.