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WINTER 2013 - Volume 60, Number 4 the Air Force Historical Foundation Founded on May 27, 1953 by Gen Carl A
WINTER 2013 - Volume 60, Number 4 WWW.AFHISTORICALFOUNDATION.ORG The Air Force Historical Foundation Founded on May 27, 1953 by Gen Carl A. “Tooey” Spaatz MEMBERSHIP BENEFITS and other air power pioneers, the Air Force Historical All members receive our exciting and informative Foundation (AFHF) is a nonprofi t tax exempt organization. Air Power History Journal, either electronically or It is dedicated to the preservation, perpetuation and on paper, covering: all aspects of aerospace history appropriate publication of the history and traditions of American aviation, with emphasis on the U.S. Air Force, its • Chronicles the great campaigns and predecessor organizations, and the men and women whose the great leaders lives and dreams were devoted to fl ight. The Foundation • Eyewitness accounts and historical articles serves all components of the United States Air Force— Active, Reserve and Air National Guard. • In depth resources to museums and activities, to keep members connected to the latest and AFHF strives to make available to the public and greatest events. today’s government planners and decision makers information that is relevant and informative about Preserve the legacy, stay connected: all aspects of air and space power. By doing so, the • Membership helps preserve the legacy of current Foundation hopes to assure the nation profi ts from past and future US air force personnel. experiences as it helps keep the U.S. Air Force the most modern and effective military force in the world. • Provides reliable and accurate accounts of historical events. The Foundation’s four primary activities include a quarterly journal Air Power History, a book program, a • Establish connections between generations. -
Lecture Notes: BCS Theory of Superconductivity
Lecture Notes: BCS theory of superconductivity Prof. Rafael M. Fernandes Here we will discuss a new ground state of the interacting electron gas: the superconducting state. In this macroscopic quantum state, the electrons form coherent bound states called Cooper pairs, which dramatically change the macroscopic properties of the system, giving rise to perfect conductivity and perfect diamagnetism. We will mostly focus on conventional superconductors, where the Cooper pairs originate from a small attractive electron-electron interaction mediated by phonons. However, in the so- called unconventional superconductors - a topic of intense research in current solid state physics - the pairing can originate even from purely repulsive interactions. 1 Phenomenology Superconductivity was discovered by Kamerlingh-Onnes in 1911, when he was studying the transport properties of Hg (mercury) at low temperatures. He found that below the liquifying temperature of helium, at around 4:2 K, the resistivity of Hg would suddenly drop to zero. Although at the time there was not a well established model for the low-temperature behavior of transport in metals, the result was quite surprising, as the expectations were that the resistivity would either go to zero or diverge at T = 0, but not vanish at a finite temperature. In a metal the resistivity at low temperatures has a constant contribution from impurity scattering, a T 2 contribution from electron-electron scattering, and a T 5 contribution from phonon scattering. Thus, the vanishing of the resistivity at low temperatures is a clear indication of a new ground state. Another key property of the superconductor was discovered in 1933 by Meissner. -
R. C. Hanna, Brother of Geoffrey Hanna 1945 Brian Pippard 1945
R. C. Hanna, brother of Geoffrey Hanna 1945 My elder brother Geoffrey graduated in 1941 along with Brian. The two of them were awarded DSIR studentships to be taken up after the war. PhD's were to be few ! Next memory is of them sharing accommodation at ADRDE Malvern with another physicist, John Robson. What talent! Two went to Canada where John measured the half life of the neutron, Geoff, with Bruno Pontecorvo, set an upper limit to the mass of the (electron) neutrino and much more. Brian I knew again when I returned to Cambridge for a PhD. He acted as compere of the entertainments presented at the Cavendish Dinner. He urged the singers to relax."This is not Bach!" I remember a couplet from one song. "And when I've ceased contributing to knowledge “Then I can be the master of a Cambridge college". Untrue ! Considering the whole of the material presented, Professor Bragg took on the role of Queen Victoria. Brian Pippard 1945 It was towards the end of the war, and an advertisement came out that Pembroke wanted to appoint some Stokes Students for research in physics; and John Ashmead (who was my superior in Malvern) suggested I should try for this. So I went in for it, and in due course I was invited for interview. There were five or six of us in the Master’s Lodge, waiting to be interviewed by the committee, which consisted of Prof. Bragg, and Prof. Todd, and Prof. Norrish, and the Master of Pembroke, and that sort of thing—pretty formidable. -
The Superconductor-Metal Quantum Phase Transition in Ultra-Narrow Wires
The superconductor-metal quantum phase transition in ultra-narrow wires Adissertationpresented by Adrian Giuseppe Del Maestro to The Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Physics Harvard University Cambridge, Massachusetts May 2008 c 2008 - Adrian Giuseppe Del Maestro ! All rights reserved. Thesis advisor Author Subir Sachdev Adrian Giuseppe Del Maestro The superconductor-metal quantum phase transition in ultra- narrow wires Abstract We present a complete description of a zero temperature phasetransitionbetween superconducting and diffusive metallic states in very thin wires due to a Cooper pair breaking mechanism originating from a number of possible sources. These include impurities localized to the surface of the wire, a magnetic field orientated parallel to the wire or, disorder in an unconventional superconductor. The order parameter describing pairing is strongly overdamped by its coupling toaneffectivelyinfinite bath of unpaired electrons imagined to reside in the transverse conduction channels of the wire. The dissipative critical theory thus contains current reducing fluctuations in the guise of both quantum and thermally activated phase slips. A full cross-over phase diagram is computed via an expansion in the inverse number of complex com- ponents of the superconducting order parameter (equal to oneinthephysicalcase). The fluctuation corrections to the electrical and thermal conductivities are deter- mined, and we find that the zero frequency electrical transport has a non-monotonic temperature dependence when moving from the quantum critical to low tempera- ture metallic phase, which may be consistent with recent experimental results on ultra-narrow MoGe wires. Near criticality, the ratio of the thermal to electrical con- ductivity displays a linear temperature dependence and thustheWiedemann-Franz law is obeyed. -
2007-2008 Physics at Brown Newsletter
Physics at Brown NEWS FOR ALUM N I an D FRIE N DS 2007 ISSUE GREETINGS FROM THE CHAIR - SP RING 2008 elcome to another issue of the Brown Physics newsletter. the rank of Associate Professor with tenure. We also report on WI wrote three years ago, during my first term as the some notable faculty achievements for the past year. department chair--with a committed faculty, dedicated staff, enthusiastic students, supportive administration, and engaged e continue the tradition of highlighting the research of alumni and friends--that the future of physics at Brown looked Wour 2007 Galkin Foundation Fellow on page 2. Also bright. Many things have taken place since then. Here we the effort in enriching our physics instruction continues. Three highlight some of the activities of the past year. new courses are offered this year and proposals for three new physics concentrations are under way. Other noteworthy 007 marked the 50th anniversary of the BCS Theory activities include WiSE, Poster Session, UTRA Awards, 2of Superconductivity. We honored Prof. Leon Resource Center, etc. In addition, community outreach Cooper with a two-day symposium on April remains a priority for the Department with a weekly 12-13. A brief description of this event is open house at Ladd and a greatly expanded five- provided on page 3. year NSF supported GK-12 program. e also report on the establishment hanks to a generous gift from his family, an Wof the Institute for Molecular and TAnthony Houghton Prize will be awarded Nanoscale Innovation, which represents an annually for the best theoretical thesis. -
Famous Physicists Himansu Sekhar Fatesingh
Fun Quiz FAMOUS PHYSICISTS HIMANSU SEKHAR FATESINGH 1. The first woman to 6. He first succeeded in receive the Nobel Prize in producing the nuclear physics was chain reaction. a. Maria G. Mayer a. Otto Hahn b. Irene Curie b. Fritz Strassmann c. Marie Curie c. Robert Oppenheimer d. Lise Meitner d. Enrico Fermi 2. Who first suggested electron 7. The credit for discovering shells around the nucleus? electron microscope is often a. Ernest Rutherford attributed to b. Neils Bohr a. H. Germer c. Erwin Schrödinger b. Ernst Ruska d. Wolfgang Pauli c. George P. Thomson d. Clinton J. Davisson 8. The wave theory of light was 3. He first measured negative first proposed by charge on an electron. a. Christiaan Huygens a. J. J. Thomson b. Isaac Newton b. Clinton Davisson c. Hermann Helmholtz c. Louis de Broglie d. Augustin Fresnel d. Robert A. Millikan 9. He was the first scientist 4. The existence of quarks was to find proof of Einstein’s first suggested by theory of relativity a. Max Planck a. Edwin Hubble b. Sheldon Glasgow b. George Gamow c. Murray Gell-Mann c. S. Chandrasekhar d. Albert Einstein d. Arthur Eddington 10. The credit for development of the cyclotron 5. The phenomenon of goes to: superconductivity was a. Carl Anderson b. Donald Glaser discovered by c. Ernest O. Lawrence d. Charles Wilson a. Heike Kamerlingh Onnes b. Alex Muller c. Brian D. Josephson 11. Who first proposed the use of absolute scale d. John Bardeen of Temperature? a. Anders Celsius b. Lord Kelvin c. Rudolf Clausius d. -
J. Robert Schrieffer Strange Quantum Numbers in Condensed Matter
Wednesday, May 1, 2002 3:00 pm APS Auditorium, Building 402, Argonne National Laboratory APS Colloquium home J. Robert Schrieffer Nobel Laureate National High Magnetic Field Laboratory Florida State University, Tallahassee [email protected] http://www.physics.fsu.edu/research/NHMFL.htm Strange Quantum Numbers in Condensed Matter Physics The origin of peculiar quantum numbers in condensed matter physics will be reviewed. The source of spin-charge separation and fractional charge in conducting polymers has to do with solitons in broken symmetry states. For superconductors with an energy gap, which is odd under time reversal, reverse spin-orbital angular momentum pairing occurs. In the fractional quantum Hall effect, quasi particles of fractional charge occur. In superfluid helium 3, a one-way branch of excitations exists if a domain wall occurs in the system. Many of these phenomena occur due to vacuum flow of particles without crossing the excitation of the energy gap. John Robert Schrieffer received his bachelor's degree from Massachusetts Institute of Technology in 1953 and his Ph.D. from the University of Illinois in 1957. In addition, he holds honorary Doctor of Science degrees from universities in Germany, Switzerland, and Israel, and from the University of Pennsylvania, the University of Cincinnati, and the University of Alabama. Since 1992, Dr. Schrieffer has been a professor of Physics at Florida State University and the University of Florida and the Chief Scientist of the National High Magnetic Field Laboratory. He also holds the FSU Eminent Scholar Chair in Physics. Before moving to Florida in 1991, he served as director for the Institute for Theoretical Physics from 1984-1989 and was the Chancellor's Professor at the University of California in Santa Barbara from 1984-1991. -
Edward Mills Purcell (1912–1997)
ARTICLE-IN-A-BOX Edward Mills Purcell (1912–1997) Edward Purcell grew up in a small town in the state of Illinois, USA. The telephone equipment which his father worked with professionally was an early inspiration. His first degree was thus in electrical engineering, from Purdue University in 1933. But it was in this period that he realized his true calling – physics. After a year in Germany – almost mandatory then for a young American interested in physics! – he enrolled in Harvard for a physics degree. His thesis quickly led to working on the Harvard cyclotron, building a feedback system to keep the radio frequency tuned to the right value for maximum acceleration. The story of how the Manhattan project brought together many of the best physicists to build the atom bomb has been told many times. Not so well-known but equally fascinating is the story of radar, first in Britain and then in the US. The MIT radiation laboratory was charged with developing better and better radar for use against enemy aircraft, which meant going to shorter and shorter wavelengths and detecting progressively weaker signals. This seems to have been a crucial formative period in Purcell’s life. His coauthors on the magnetic resonance paper, Torrey and Pound, were both from this lab. I I Rabi, the physicist who won the 1944 Nobel Prize for measuring nuclear magnetic moments by resonance methods in molecular beams, was the head of the lab and a major influence on Purcell. Interestingly, Felix Bloch (see article on p.956 in this issue) was at the nearby Radio Research lab but it appears that the two did not interact much. -
I. I. Rabi Papers [Finding Aid]. Library of Congress. [PDF Rendered Tue Apr
I. I. Rabi Papers A Finding Aid to the Collection in the Library of Congress Manuscript Division, Library of Congress Washington, D.C. 1992 Revised 2010 March Contact information: http://hdl.loc.gov/loc.mss/mss.contact Additional search options available at: http://hdl.loc.gov/loc.mss/eadmss.ms998009 LC Online Catalog record: http://lccn.loc.gov/mm89076467 Prepared by Joseph Sullivan with the assistance of Kathleen A. Kelly and John R. Monagle Collection Summary Title: I. I. Rabi Papers Span Dates: 1899-1989 Bulk Dates: (bulk 1945-1968) ID No.: MSS76467 Creator: Rabi, I. I. (Isador Isaac), 1898- Extent: 41,500 items ; 105 cartons plus 1 oversize plus 4 classified ; 42 linear feet Language: Collection material in English Location: Manuscript Division, Library of Congress, Washington, D.C. Summary: Physicist and educator. The collection documents Rabi's research in physics, particularly in the fields of radar and nuclear energy, leading to the development of lasers, atomic clocks, and magnetic resonance imaging (MRI) and to his 1944 Nobel Prize in physics; his work as a consultant to the atomic bomb project at Los Alamos Scientific Laboratory and as an advisor on science policy to the United States government, the United Nations, and the North Atlantic Treaty Organization during and after World War II; and his studies, research, and professorships in physics chiefly at Columbia University and also at Massachusetts Institute of Technology. Selected Search Terms The following terms have been used to index the description of this collection in the Library's online catalog. They are grouped by name of person or organization, by subject or location, and by occupation and listed alphabetically therein. -
Appendix E Nobel Prizes in Nuclear Science
Nuclear Science—A Guide to the Nuclear Science Wall Chart ©2018 Contemporary Physics Education Project (CPEP) Appendix E Nobel Prizes in Nuclear Science Many Nobel Prizes have been awarded for nuclear research and instrumentation. The field has spun off: particle physics, nuclear astrophysics, nuclear power reactors, nuclear medicine, and nuclear weapons. Understanding how the nucleus works and applying that knowledge to technology has been one of the most significant accomplishments of twentieth century scientific research. Each prize was awarded for physics unless otherwise noted. Name(s) Discovery Year Henri Becquerel, Pierre Discovered spontaneous radioactivity 1903 Curie, and Marie Curie Ernest Rutherford Work on the disintegration of the elements and 1908 chemistry of radioactive elements (chem) Marie Curie Discovery of radium and polonium 1911 (chem) Frederick Soddy Work on chemistry of radioactive substances 1921 including the origin and nature of radioactive (chem) isotopes Francis Aston Discovery of isotopes in many non-radioactive 1922 elements, also enunciated the whole-number rule of (chem) atomic masses Charles Wilson Development of the cloud chamber for detecting 1927 charged particles Harold Urey Discovery of heavy hydrogen (deuterium) 1934 (chem) Frederic Joliot and Synthesis of several new radioactive elements 1935 Irene Joliot-Curie (chem) James Chadwick Discovery of the neutron 1935 Carl David Anderson Discovery of the positron 1936 Enrico Fermi New radioactive elements produced by neutron 1938 irradiation Ernest Lawrence -
JUAN MANUEL 2016 NOBEL PEACE PRIZE RECIPIENT Culture Friendship Justice
Friendship Volume 135, № 1 Character Culture JUAN MANUEL SANTOS 2016 NOBEL PEACE PRIZE RECIPIENT Justice LETTER FROM THE PRESIDENT Dear Brothers, It is an honor and a privilege as your president to have the challenges us and, perhaps, makes us question our own opportunity to share my message with you in each edition strongly held beliefs. But it also serves to open our minds of the Quarterly. I generally try to align my comments and our hearts to our fellow neighbor. It has to start with specific items highlighted in each publication. This with a desire to listen, to understand, and to be tolerant time, however, I want to return to the theme “living our of different points of view and a desire to be reasonable, Principles,” which I touched upon in a previous article. As patient and respectful.” you may recall, I attempted to outline and describe how Kelly concludes that it is the diversity of Southwest’s utilization of the Four Founding Principles could help people and “treating others like you would want to be undergraduates make good decisions and build better treated” that has made the organization successful. In a men. It occurred to me that the application of our values similar way, Stephen Covey’s widely read “Seven Habits of to undergraduates only is too limiting. These Principles are Highly Effective People” takes a “values-based” approach to indeed critical for each of us at this particularly turbulent organizational success. time in our society. For DU to be a successful organization, we too, must As I was flying back recently from the Delta Upsilon be able to work effectively with our varied constituents: International Fraternity Board of Directors meeting in undergraduates, parents, alumni, higher education Arizona, I glanced through the February 2017 edition professionals, etc. -
Introduction to Unconventional Superconductivity Manfred Sigrist
Introduction to Unconventional Superconductivity Manfred Sigrist Theoretische Physik, ETH-Hönggerberg, 8093 Zürich, Switzerland Abstract. This lecture gives a basic introduction into some aspects of the unconventionalsupercon- ductivity. First we analyze the conditions to realized unconventional superconductivity in strongly correlated electron systems. Then an introduction of the generalized BCS theory is given and sev- eral key properties of unconventional pairing states are discussed. The phenomenological treatment based on the Ginzburg-Landau formulations provides a view on unconventional superconductivity based on the conceptof symmetry breaking.Finally some aspects of two examples will be discussed: high-temperature superconductivity and spin-triplet superconductivity in Sr2RuO4. Keywords: Unconventional superconductivity, high-temperature superconductivity, Sr2RuO4 INTRODUCTION Superconductivity remains to be one of the most fascinating and intriguing phases of matter even nearly hundred years after its first observation. Owing to the breakthrough in 1957 by Bardeen, Cooper and Schrieffer we understand superconductivity as a conden- sate of electron pairs, so-called Cooper pairs, which form due to an attractive interaction among electrons. In the superconducting materials known until the mid-seventies this interaction is mediated by electron-phonon coupling which gises rise to Cooper pairs in the most symmetric form, i.e. vanishing relative orbital angular momentum and spin sin- glet configuration (nowadays called s-wave pairing). After the introduction of the BCS concept, also studies of alternative pairing forms started. Early on Anderson and Morel [1] as well as Balian and Werthamer [2] investigated superconducting phases which later would be identified as the A- and the B-phase of superfluid 3He [3]. In contrast to the s-wave superconductors the A- and B-phase are characterized by Cooper pairs with an- gular momentum 1 and spin-triplet configuration.