DOCSLIB.ORG

Kondo Coupling, Hyperfine and Exchange Interactions J

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Kondo Coupling, Hyperfine and Exchange Interactions J KONDO COUPLING, HYPERFINE AND EXCHANGE INTERACTIONS J. Flouquet To cite this version: J. Flouquet. KONDO COUPLING, HYPERFINE AND EXCHANGE INTERACTIONS. Journal de Physique Colloques, 1978, 39 (C6), pp.C6-1493-C6-1498. 10.1051/jphyscol:19786592. jpa-00218085 HAL Id: jpa-00218085 https://hal.archives-ouvertes.fr/jpa-00218085 Submitted on 1 Jan 1978 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. JOURNAL DE PHYSIQUE Colloque C6, suppf6ment au no 8, Tome 39, aotit 1978, page C6-1493 KONDO COUPLING, HYPERFINE AND EXCHANGE INTERACTIONS J. Flouquet Centre de Recherches sup Zes Tr're's Basses Tern graixres, C.N.R.S., B.P. 166 X, 38042 Grenoble Cedex, - Lance - Rdsum6.- Premisrement, la possibilitd d'observer une structure hyperfine dans un alliage dilud est discutde suivant la force du couplage Kondo ; d'autres exemples de structures internes du moment lo- calis6 sont montrds. Deuxismement, les propri6t6s remarquables des compos&s anormaux de c6rium sont ddcrites ; leur lien avec le comportement Kondo d'une impuretd isolde est discutd. Abstract.- Firstly, the possible observation of an hyperfine structure in dilute alloys is discussed in function of the strength of the Kondo coupling ; other examples of inner structures of the local moment are given. Secondly, the striking properties of the abnormal rare earth compounds of cerium are reported ; their relations with the Kondo behaviour of an isolated impurity are discussed. The study of dilute alloys of magnetic impu- proportional to the magnetization. Such situ- [H hf- -1 rities has experienced a burst of activity in recent ations have been observed for the 2 Cr, Co, & years mainly in connection with the elucidation of Co alloys 141. the Kondo problem /1,2/. Currently, an attempt is At the opposite extreme for k T < A (the B K made to observe and understand the inner structureof weak coupling case), the nuclear and the electronic +++ the 3d and 4f impurities when the k-d or k-f mixing spin must be coupled first : F = I + S. When a well with the conduction electrons is not weak that is to isolated ground state F can be defined, the Kondo say when the initial ionic levels of the configura- Hamiltonian is only a perturbing term. Its initial tion may be strongly perturbed by interactions with form, given by the well-known expression : the Fermi Sea 131. An other open question is the relation between the Kondo behaviour found for a ra- where s is the spin of the conduction electrons, may re earth impurity like Ce and the abnormal proper- be reduced to : ties discovered in some corresponding intermetallic + -+ compounds. I will report simple results obtained in HTe=aJF.s (1) each direction at Orsay and Grenoble. The striking result is that a Kondo coupling (J > 0) may appear or disappear due only to the action of 1. THE HYPERFINE COUPLING AND THE KONDO COWLING.- the hyperfine coupling when I and S are antiferro- Experiments performed at low temperature down to 3 mK magnetically coupled. For example for A > 0, S < I by nuclear orientation (N.0) /5/ have clearly shown leads to a reversed sign of the exchange coupling that when the localized moment of spin S has an hy- 1 and S = I = - to the spectacular case of a singlet 2 perfine coupling A with its nucleus of spin I : + + electron nuclear ground state. Finally, we point out Hhf=AI. S that generally the change in the degeneracy of the two different regimes occur according as the hyper- magnetic levels must change its Kondo coupling and fine coupling is greater or lower than the Kondo the other properties linked to the exchange coupling coupling (A kTK) For kBTK > A (the strong cou- 3 . like the ordering spin glass temperature, the depres- pling case), the local moment is strongly coupled to sion of the superconductive transition. (These phe- the conduction electrons via the Kondo coupling. At nomena are basically the same that occurs for 4f low temperature (T < TK), the polarization of the ions when the crystal field levels becomes depopu- singlet ground state is described by a pure elec- lated 141). A nice experiment would be to study at tronic term ; the hyperfine coupling can be regarded very low temperature how the Kondo coupling is re- as a perturbation and can be reduced to : lated to the parameters of differentisotopes. Hhf = A <SZ> IZ For 3d impurities weak coupling cases have been observed for &Mn, Fr, EMn alloys in N.0 The nuclear and electronic term are uncou- experiments, for abmrmal 4f ions for &Yb, pled. The nucleisee an effectivehyperfine field %r, Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:19786592 C6-1494 JOURNAL DE PHYSIQUE alloys. An excellent example is provided by the stu- the virtual level relative to the Fermi level to its dy of the &Yb alloys made in Grenoble on different width A is lower than - 1. isotopes of Ytterbium. From E.P.R., Miissbauer, N.O. experiments 141, it is well-known that &Yb fullfills the condition of a weak coupling regime (J > 0, A > kT ). A favorable situation is realized as the K element Yb has a number of stable isotopes with a Large variety of nuclear parameters. As indicatedin the table (I), the 17'Yb isotope has no nuclear spin; the 171Yb and 173 Yb isotopes have moments of oppo- site sign and furthermore the former isotope full- fills the conditions for electron nuclear singlet 1 coupling (A > 0, S = I = -). Since the susceptibi- 2 lity x of 174~balloys follows a pure Curie lawdown 7 mK which corresponds to the r7 electronic doublet ground state, the &17' Yb susceptibility showsstrong departures form this behaviour at low temperature /5/. Below 100 mK, a constant susceptibility law is observed in agreement with the formation of a sin- glet electron nuclear ground state. This observa- Fig. 1 : Resistivity of &171Yb and &17'yb. The so- tion is no more than the well-known Breit-Rabi ef- lid line is a straight forward transposi- tion of the pairs of impurities fect in atamic physics. 2. THE HYPERFINE COUPLING AND THE MAGNETISM' S ORIGIN. - Table I The situation is more complex when the position of Nuclear spin and hyperfine coupling of different Yb isotopes dissolved in gold r the virtual level is closer to the Fermi level as it occurs for most 3d ions (Eo/A>-1). The sign and ma- gnitude of the hyperfine coupling are relevant to the magnetism's origin as the hyperfine contribu- tions of the spin and orbital magnetism have oppo- Ain mK 128 - 35 site contributions withdifferent magnitudes : for a Co2* ion, the orbital hyperfine term is near + 700 kOe per yB, the spin term near - 100 kOe per The corresponding electrical resistivity of ug. The occurence of an orbital magnetism has often the monoisotopic alloys have been measured down to been understood as a proof of the validity of an 18 mK 1'61. As predicted by the relation (I), a re- ionic description as following the Friedel Anderson sistivity drop is observed in the &I7' Yb alloys picture it was generally admitted that only the con- below the hyperfine splitting equal to 128 mK. A dition of spin magnetism is fullfilled for 3d ions : straight forward transposition of the problem ofthe the k-d mixing may quench the orbital momentum. resistivity given by the formation of pairs of im- The observation of orbital effects is now purities in Kondo systems /lo/ leads to a good des- well-established notably for Co ions in Au, Cu, W, cription of the experimental behaviour even in the Mo, Pd (see references /4/).,We will only discuss crossover regime A % kT (figure 1). the striking case of the goalloy where an orbital These experiments show that the hyperfine contribution is clearly seen in hyperfine and trans- coupling is observed in static and transport measu- port properties. (Notably in the dilute limit of the rements-provide A > kTK . Here, the good comparison magnetic ions, the anisotropy of the magnetoresis- between the intraconfiguration parameter A andthek-d tance, defined as the difference of the magnetoresis- or k-f mixing is the Kondo coupling. The situation tance measured parallel and perpendicular to the is rather simple as the 4f level Yb in &Yb and the current, occurs only for a non spherical state). 3d levels in the reported examples are far below The first column in table I1 represents the the Fermi level : the ratio of the energy, Eo, of hyperfine field measured for the three last 3d ions' show clearly that an abnormal behaviour occurs, it has been interpreted as the manifestation of a Kondo coupling, a fine structure and a relaxation effect on the intermediate Fe level. Clearly experiments on single crystal must be performed to rule out the occurence of a crystalline anisotropy; it must be pointed out that the broad NMR linewidth observed for Co and Ni is unexplained as well as the diffe- rence between the hyperfine field detected by N.O. (+ 210 kOe) and by NMR (+ 240 kOe) /4/. Table I1 Experimental hyperfine field of GFe, Co, Ni and comparison with the theoretical value assuming the ionic levels described in the text in kOe %f %f -PdFe - 300 + 78 -PdCo + 240 + 240 .g.
Load more

Recommended publications
  • Nuclear Energy Agency Nuclear Data Committee
    NUCLEAR ENERGY AGENCY NUCLEAR DATA COMMITTEE SUMMARY RECORD OF THE lWEEFPY-FIRST MEETING (Technical Sessions) CBNM, Gee1 (Belgium) 24th-28th September 1979 Compiled by C. COCEVA (Scientific Secretary) OECD NUCLEAR ENERGY AGENCY 38 Bd. Suchet, 75016 Paris TABLE OF CONTENTS TECHNICAL SESSIONS Participants in meeting 1. Isotopes 2. National Progress Reports 3. Meetings 4. Technical Discussions 5. Topical Meeting on "Progress in Neutron Data of Structural Materials for Fast ~eactors" 6. Neutron and Related Nuclear Data Compilations and Evaluations Appendices 1 Meetings of the IAEA/NDS planned for 1980, 1981 and 1982 2 Progranme of the Topical Meeting on "Progress in Neutron Data of Structural Materials for Fast Reactors " 3 Summary of the general discussion on the works presented at the Topical Meeting TECmTICAL SESSIONS Perticipants in the 21st Meeting were as follows : For Canada : Dr. W.G. Cross Atomic Energy of Canada Ltd. Chalk River For Japan : Dr. K. Tsukada Japan Atomic Energy Research Institute Tokai-blur a For the United States of America : Dr. R.E. Chrien (Chairman) Brookhaven National Laboratory Dr. S.L. Wl~etstone U.S. Department of Energy Dr. 8.T. Motz Los Alamos Scientific Laboratory Dr. F.G. Perey Oak Ridge National Laboratory For the countries of the European Communities and the European Commission acting together : Dr. R. Iiockhoff (Local Secretary) Central Bureau for Nuclear Pleasurements Geel, Belgium Dr. C. Coceva (Scientific Secretary) Comitato Nazionale per 1'Energia Nucleare Bologna, Italy Dr. S. Cierjacks Kernforschungszentrum Karlsruhe Federal Republic of Germany Dr. C. Fort Conunissariat i 1'Energie Atomique Cadaroche, France Dr. A. Michaudon (Vice-chairman) Commissariat 2 1'Energie Atomique Bruysrcs-1.e-ChZtel Dr.
    [Show full text]
  • Metastable Non-Nucleonic States of Nuclear Matter: Phenomenology
    Physical Science International Journal 15(2): 1-25, 2017; Article no.PSIJ.34889 ISSN: 2348-0130 Metastable Non-Nucleonic States of Nuclear Matter: Phenomenology Timashev Serge 1,2* 1Karpov Institute of Physical Chemistry, Moscow, Russia. 2National Research Nuclear University MEPhI, Moscow, Russia. Author’s contribution The sole author designed, analyzed and interpreted and prepared the manuscript. Article Information DOI: 10.9734/PSIJ/2017/34889 Editor(s): (1) Prof. Yang-Hui He, Professor of Mathematics, City University London, UK And Chang-Jiang Chair Professor in Physics and Qian-Ren Scholar, Nan Kai University, China & Tutor and Quondam-Socius in Mathematics, Merton College, University of Oxford, UK. (2) Roberto Oscar Aquilano, School of Exact Science, National University of Rosario (UNR),Rosario, Physics Institute (IFIR)(CONICET-UNR), Argentina. Reviewers: (1) Alejandro Gutiérrez-Rodríguez, Universidad Autónoma de Zacatecas, Mexico. (2) Arun Goyal, Delhi University, India. (3) Stanislav Fisenko, Moscow State Linguistic University, Russia. Complete Peer review History: http://www.sciencedomain.org/review-history/20031 Received 17 th June 2017 Accepted 8th July 2017 Original Research Article th Published 13 July 2017 ABSTRACT A hypothesis of the existence of metastable states for nuclear matter with a locally shaken-up nucleonic structure of the nucleus, was proposed earlier. Such states are initiated by inelastic scattering of electrons by nuclei along the path of weak nuclear interaction. The relaxation of such nuclei is also determined by weak interactions. The use of the hypothesis makes it possible to physically interpret a rather large group of experimental data on the initiation of low energy nuclear reactions (LENRs) and the acceleration of radioactive α- and β-decays in a low-temperature plasma.
    [Show full text]
  • CROSS SECTIONS of (N,P), (N,Α), (N,2N) REACTIONS on ISOTOPES
    CROSS SECTIONS OF (n, p), (n, α), (n, 2n) REACTIONS ON ISOTOPES OF Dy, Er, Yb AT En= 14.6 MEV А.O. Kadenko, O.M. Gorbachenko, V.A. Plujko, G.I. Primenko Nuclear Physics Department, Taras Shevchenko National University, Kyiv, Ukraine Abstract The cross sections of the neutron reactions at En= 14.6 MeV on the isotopes of Dy, Er, Yb with emission of neutrons, proton and alpha-particle were studied by the use of new experimental data and different theoretical approaches. New and improved experimental data were obtained by the neutron- activation technique. Present experimental results and evaluated nuclear data from EXFOR, TENDL, ENDF data libraries were compared with different systematics and calculations within codes of EMPIRE 3.0 and TALYS 1.2. Contribution of pre-equilibrium decay was studied. The recommendations on validity of different systematics for estimations of cross-sections of considered reactions are given. 1. Introduction Studies of the nuclear reaction cross sections induced by neutrons provides an opportunity to get information on the excited states of atomic nuclei and nuclear reaction mechanisms [1]. In addition, nuclear reaction cross section data are necessary in applied applications such as the design of fusion reactors protection and modernization of existing nuclear power plants [2, 3]. In particular, they allow to calculate the activity and the degree of radiation damage to structural elements of nuclear reactors [3]. Practical interest in cross sections of nuclear reactions caused by their wide use in experimental nuclear physics methods, such as the method of boundary indicators in measuring the spectrum of neutrons in the reactor core of a nuclear reactor, or neutron activation analysis.
    [Show full text]
  • Abstract Ultracold Mixtures of Rubidium and Ytterbium
    ABSTRACT Title of dissertation: ULTRACOLD MIXTURES OF RUBIDIUM AND YTTERBIUM FOR OPEN QUANTUM SYSTEM ENGINEERING Creston David Herold, Doctor of Philosophy, 2014 Dissertation directed by: Dr. James Porto and Professor Steven Rolston Joint Quantum Institute, University of Maryland Department of Physics and National Institute of Standards and Technology Exquisite experimental control of quantum systems has led to sharp growth of basic quantum research in recent years. Controlling dissipation has been crucial in producing ultracold, trapped atomic samples. Recent theoretical work has suggested dissipation can be a useful tool for quantum state preparation. Controlling not only how a system interacts with a reservoir, but the ability to engineer the reservoir itself would be a powerful platform for open quantum system research. Toward this end, we have constructed an apparatus to study ultracold mixtures of rubidium (Rb) and ytterbium (Yb). We have developed a Rb-blind optical lattice at λzero = 423:018(7) nm, which will enable us to immerse a lattice of Yb atoms (the system) into a Rb BEC (superfluid reservoir). We have produced Bose-Einstein condensates of 170Yb and 174Yb, two of the five bosonic isotopes of Yb, which also has two fermionic isotopes. Flexible optical trapping of Rb and Yb was achieved with a two-color dipole trap of 532 and 1064 nm, and we observed thermalization in ultracold mixtures of Rb and Yb. Using the Rb-blind optical lattice, we measured very small light shifts of 87Rb BECs near the λzero wavelengths adjacent the 6p electronic states, through a coherent series of lattice pulses. The positions of the λzero wavelengths are sensitive to the electric dipole matrix elements between the 5s and 6p states, and we made the first experimental measurement of their strength.
    [Show full text]
  • Detection of Elements at All Three R-Process Peaks in the Metal-Poor Star HD 160617
    Published in the Astrophysical Journal A Preprint typeset using LTEX style emulateapj v. 5/2/11 DETECTION OF ELEMENTS AT ALL THREE R-PROCESS PEAKS IN THE METAL-POOR STAR HD 1606171 ,2 ,3 Ian U. Roederer4 and James E. Lawler5 Published in the Astrophysical Journal ABSTRACT We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 160617. These elements include arsenic and selenium, which have not been detected previously in halo stars, and the elements tellurium, osmium, iridium, and platinum, which have been detected previously. Absorption lines of these elements are found in archive observations made with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. We present up-to-date absolute atomic transition probabilities and complete line component patterns for these elements. Additional archival spectra of this star from several ground-based instruments allow us to derive abundances or upper limits of 45 elements in HD 160617, including 27 elements produced by neutron-capture reactions. The average abundances of the elements at the three r-process peaks are similar to the predicted solar system r-process residuals when scaled to the abundances in the rare earth element domain. This result for arsenic and selenium may be surprising in light of predictions that the production of the lightest r-process elements generally should be decoupled from the heavier r-process elements. Subject headings: atomic data — nuclear reactions, nucleosynthesis, abundances — stars: abundances — stars: individual (HD 160617) — stars: Population II 1. INTRODUCTION in greater abundance during n-capture reactions. The Understanding the origin of the elements is one of the s-process path closely follows the valley of β-stability, major challenges of modern astrophysics.
    [Show full text]
  • Fi Oooc U 1999 3 1 / 40
    fi OooC PL0002050 ISSN 1425-204X INSTITUTE OF NUCLEAR CHEMISTRY AND TECHNOLOGY SL ¥ u 1999 31/ 40 Please be aware that all of the Missing Pages in this document were originally blank pages EDITORS Wiktor Smuiek, Ph.D. Ewa Godlewska-Para PRINTING Sylwester Wojtas © Copyright by the Institute of Nuclear Chemistry and Technology, Warszawa 2000 All rights reserved CONTENTS GENERAL INFORMATION 9 MANAGEMENT OF THE INSTITUTE 11 MANAGING STAFF OF THE INSTITUTE 11 HEADS OF THE INCT DEPARTMENTS 11 SCIENTIFIC COUNCIL (1999-2003) 11 SCIENTIFIC STAFF 14 PROFESSORS 14 ASSOCIATE PROFESSORS 14 SENIOR SCIENTISTS (Ph.D.) 14 RADIATION CHEMISTRY AND PHYSICS, RADIATION TECHNOLOGIES 17 GENERATION OF RADICAL CATIONS FROM PHENYL, VINYL, AND ALLYL CONTAINING THIOETHERS IN ORGANIC SOLVENTS A. Korzeniowska-Sobczuk, P. Wiśniewski, K. Bobrowski, L. Richter, O. Brede 19 EPR STUDIES OF RADICALS INDUCED BY IONISING RADIATION IN FLUTAMIDE H.B. Ambroż, E. Kornacka, G. Przybytniak 20 THE ROLE OF Cu(I) AND Cu(II) IN DNA DAMAGES H.B. Ambroż, E. Kornacka, G. Przybytniak 21 TEMPERATURE COEFFICIENT OF THE RADIATION YIELD OF THE RADICAL CH3 • CH COf IN CRYSTALLINE ALANINĘ Z.P. Zagórski 22 COMPETITION BETWEEN INTRAMOLECULAR TWO-CENTERED THREE-ELECTRON BONDED (S. • .S)+ AND (S. • .N)+ FORMATION DURING PHOTOOXIDATION OF METHIONINE-CONTAINING PEPTIDES BY THE 4-CARBOXYBENZOPHENONE TRIPLET STATE IN AQUEOUS SOLUTION K. Bobrowski, G.L. Hug, H. Kozubek, B. Marciniak 23 Trp[NH ' +] -Tyr[O ' ] RADICAL TRANSFORMATION IN H-Trp-(Pro)n-Tyr-OH,n = 3-5, SERIES OF PEPTIDES K. Bobrowski, J. Poznański, J. Holcman, K.L. Wierzchowski 25 EPR OF METALS NANOPARTICLES IN MCM-41 MOLECULAR SIEVES J.
    [Show full text]
  • Optical Frequency Measurement and Ground State Cooling of Single Trapped Yb+ Ions
    Optical frequency measurement and ground state cooling of single trapped Yb+ ions Peter Blythe March 2004 with updates and corrections August 2005 Submitted in partial ful¯lment of the requirements for the degree of Doctor of Philosophy of the University of London Abstract The thesis describes experiments on single laser-cooled ions of Yb+ in a radiofrequency ion trap. 2 2 The ion is laser-cooled on the 369 nm S1=2! P1=2 electric dipole tran- 2 2 sition, and high resolution spectroscopy of the 467 nm S1=2! F7=2 electric octupole `clock' transition has been performed. The 467 nm transition can be used as an optical frequency standard. To this end, several absolute optical frequency measurements of the F = 171 + 0; mF = 0 ! F = 3; mF = 0 component in Yb have been made with a femtosecond laser frequency comb generator. The comb was referenced to a hydrogen maser which forms part of the clock ensemble used to generate the UTC(NPL) timescale. During the work described in this thesis, the linewidth of the 467 nm probe laser has been narrowed from 4 kHz to 200 Hz, increasing the measurement resolution. The frequency measurements have been supported by a full investigation of the systematic frequency shifts of the octupole transition, including the AC Stark, second-order Zeeman, quadrupole, DC Stark, second-order Doppler and blackbody shifts. Cooling an ion of 172Yb+ to the ground motional state of the ion trap by `EIT cooling' on the 369 nm transition has been investigated, both by numerical simulation and experiment. A new technique for measuring the temperature of a trapped ion without the use of a narrow transition has been developed.
    [Show full text]
  • A Two-Orbital Quantum Gas with Tunable Interactions
    A two-orbital quantum gas with tunable interactions Moritz Höfer München 2017 A two-orbital quantum gas with tunable interactions Dissertation an der Fakultät für Physik Ludwig-Maximilians-Universität München vorgelegt von Moritz Höfer aus Stade München, den 02. März 2017 Tag der mündlichen Prüfung: 7. April 2017 Erstgutachter: Prof. Immanuel Bloch Zweitgutachter: Prof. Wilhelm Zwerger Weitere Prüfungskommissionsmitglieder: Prof. A. Högele, Prof. M. Punk Zusammenfassung Im letzten Jahrzehnt haben sich Quantengasexperimente als gut kontrollierbare Modell- systeme zur Untersuchung komplexer Fragestellungen aus diversen Bereichen der Physik etabliert. Ultrakalte Quantengase zeichnen sich insbesondere dadurch aus, dass sie einen direkten und experimentell einfach realisierbaren Zugang zu ihrer Wechselwirkung bieten. Das gezielte Einstellen der Wechselwirkungsstärke und die Erforschung der daraus resul- tierenden Aggregatzustände erlaubt es ein tiefes Verständnis der kondensierten Materie zu gewinnen. Insbesondere erdalkaliähnliche Atome wie Ytterbium bieten die Möglich- keit Phänomene der Festkörperphysik zu untersuchen, die durch die Wechselwirkung von Elektronen in verschiedenen Orbitalen oder durch eine größere Rotationssymmetrie des Spins als in gewöhnlichen Spin-1/2 Systemen hervorgerufen werden. Diese Doktorarbeit präsentiert die experimentelle Charakterisierung der Wechselwir- kung ultrakalter, fermionischer Ytterbium-Atome (173Yb) in verschiedenen elektronischen Orbitalen. Dabei wird nachgewiesen, dass sich die Wechselwirkungsstärke
    [Show full text]
  • Quantum Nanophotonics with Ytterbium in Yttrium Orthovanadate
    Quantum nanophotonics with ytterbium in yttrium orthovanadate Thesis by Jonathan Miners Kindem In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2019 Defended March 14, 2019 ii © 2019 Jonathan Miners Kindem ORCID: 0000-0002-7737-9368 All rights reserved. iii ACKNOWLEDGEMENTS Thank you Andrei for being such a wonderful advisor throughout my time at Cal- tech. Your enthusiasm and excitement for doing science is contagious. Thanks for your patience as I climbed out of various “pits of incompetency" over the years and for having a good sense of humor. Thank you for setting high expectations for our work while giving me freedom in the lab to pursue things I found interesting. It’s been a lot of fun. Thank you to the Faraon group: Tian for getting me up to speed in the lab and teaching me so much over the years. Evan for all the late-night chats in the office and trips to the climbing gym. John for always being willing to answer “quick questions” that were never really quick questions and for your enthusiasm for rare- earths. Jake for keeping the rare-earth ego in check and for fabricating nanobeams. Andrei R. for bringing a fresh set of eyes to the experiment and for the fun times getting the singles measurements working. I’m glad to be leaving the experiment in good hands and look forward to seeing where experiments go in the future. Ioana for always being a source of positivity in lab and for letting me monopolize the fridge over the last few months.
    [Show full text]
  • Production and Chemical Processing of 177Lu for Nuclear Medicine at the Munich Research Reactor FRM-II
    Institut f¨urRadiochemie Production and chemical processing of 177Lu for nuclear medicine at the Munich research reactor FRM-II Dissertation of Zuzana Dvoˇr´akov´a Technische Universit¨atM¨unchen Institut f¨urRadiochemie der Technischen Universit¨atM¨unchen Production and chemical processing of 177Lu for nuclear medicine at the Munich research reactor FRM-II Zuzana Dvoˇr´akov´a Vollst¨andiger Abdruck der von der Fakult¨at f¨urChemie der Technischen Universit¨atM¨unchen zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften (Dr. rer. nat.) genehmigten Dissertation. Vorsitzender: Univ.-Prof. Dr. Dr. h. c. B. Rieger Pr¨ufer der Dissertation: 1. Univ.-Prof. Dr. A. T¨urler 2. Univ.-Prof. Dr. K. K¨ohler Die Dissertation wurde am 13.8.2007 bei der Technischen Universit¨at M¨unchen eingere- icht und durch die Fakult¨at f¨urChemie am 20.9.2007 angenommen. Abstract The main goal of the present dissertation was to investigate the feasibility of pro- ducing the radionuclide 177Lu at the Munich research reactor FRM-II. Lutetium-177 represents an ideal therapeutic radioisotope with suitable chemical properties and nuclear decay characteristics. Radiopharmaceuticals containing 177Lu are currently under development and tested for the treatment of various cancers in dozens of clin- ical trials around the world. The radionuclide 177Lu can be produced either directly by the 176Lu(n, γ)177Lu β− reaction or indirectly by the 176Yb(n, γ)177Yb → 177Lu reaction. The irradiation yield of 177Lu in both production routes was experimentally determined and compared with theoretical calculations. A reliable method for the calculation of the 177Lu yield, based on the Westcott convention, was established, which is more accurate than the methods published in the literature.
    [Show full text]
  • T H Is D Is S E R Ta Tio N Has Been G1—5072 M Ic R O F Ilm E D E X Actly As
    This dissertation has been G1—5072 microfilmed exactly as received BOWMAN, Jr., George Br'ice, 1932- DECON TAMIN ATION OF SOME SE EEC TED BABE EARTH ISOTOPES AND T1IE GAMMA RADIATIONS OF HAFNIUM-172 AND -173. The Ohio State University, Ph.D., 1961 Physics, nuclear University Microfilms, Inc., Ann Arbor, Michigan IECQNTAMINATICffi OF SOME SELECTED RARE EARTH ISOTOPES AMD THE GAMMA RADIATIONS OP HAIOTUM-172 AND -175 DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By George Price Bovaan, Jr., B. S., A. K. Capt&in, United States Air Force The Ohio State University 1961 Approved hy J / / A .......* / -it. i ..-'.v Adviser Department of Chemistry ■ ■ IV. .1 1 . ^ ^ .i.i A dviser Department of Physics ACXNCWIEDGMEHT The author wishes to express his appreciation to Professor M. H. Kurbatov and Professor J. D. Kurbatov for their guidance in this research, to Hr. H. J. Sathoff and Mr. P. J. Bradley for their assistance in collecting- the data, and to the United States Air Force for providing the opportunity for him to pursue this course of study. ii CONTENTS CHAPTER Page I CHEMICAL PURIFICATION OF SEIECTED RARE EARTH ISOTOPES . 1 Description of Cation-Exchange Columns ................................. 3 General Chemical Procedure for Decontamination of the Enriched Isotope Samples .................................................... 8 Chemical Procedure Flow Sheet .................................................... 11 P u rific a tio n of Neodymium-144 S a m p l e ................................. 12 P u rific a tio n of I>yspro3iui[h*156 S a m p l e ........................................14 Purification of Erbiunwl62 Sample ......
    [Show full text]
  • Isotopic Separation and Spectroscopy of Ytterbium-173(3/2) Using Laser Cooling
    Isotopic Separation and Spectroscopy of Ytterbium-173(3/2) using Laser Cooling Quinton Dayle McKnight A senior thesis submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Bachelor of Science Scott Bergeson, Advisor Department of Physics and Astronomy Brigham Young University Copyright © [2019] Quinton Dayle McKnight All Rights Reserved ABSTRACT Isotopic Separation and Spectroscopy of Ytterbium-173(3/2) using Laser Cooling Quinton Dayle McKnight Department of Physics and Astronomy, BYU Bachelor of Science A multi-laser approach is used in which we correct errors in the atomic spectroscopy that seriously compromised previous measurements by another group [Phys. Rev. A 76, 062505 (2007)]. 173 1 o 0 We report precision measurements of the Yb 6s6p P1 (F = 3=2;7=2) transition frequencies. We use a frequency comb to determine the laser frequency. Our work completes a set of isotope- and hyperfine-shift measurements reported in [1], published by our group. The frequency shift between 1 o 0 3 7 the 6s6p P1 (F = 2 ; 2 ) levels is 86:29 ± 0:77 MHz. The uncertainty is dominated by quantum interference effects in the excitation and decay pathways. Appendix A is a summary of notes made on an overheating problem encountered in our laboratory, and a copy of both papers on which I was primary author while completing my undergraduate work included at the end of the thesis. Keywords: [quantum interference, optical pumping, spectroscopy, optical molasses, laser-induced fluorescence, ytterbium ] ACKNOWLEDGMENTS This research was supported by Brigham Young University and by grants from the National Science Foundation under Grant No.
    [Show full text]