September 16, 2014
Alain Aspect,
Institut d'Optique, Palaiseau
Host:
Pisin Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
From Einstein’s intuition to quantum bits:
a new quantum age
Abstract
In 1935, with co-authors Podolsky and Rosen, Einstein discovered a weird quantum situation, in which particles in a pair are so strongly correlated that Schrödinger called them “entangled”. By analyzing that situation, Einstein concluded that the quantum formalism was incomplete. Niels Bohr immediately opposed that conclusion, and the debate lasted until the death of these two giants of physics.
In 1964, John Bell discovered that it is possible to settle the debate experimentally, by testing the famous "Bell's inequalities", and to show directly that the revolutionary concept of entanglement is indeed a reality.
Based on that concept, a new field of research has emerged, quantum information, where one uses quantum bits, the so-called “qubits”, to encode the information and process it. Entanglement between qubits enables conceptually new methods for processing and transmitting information. Large-scale practical implementation of such concepts might revolutionize our society, as did the laser, the transistor and integrated circuits, some of the most striking fruits of the first quantum revolution, which began with the 20th century. To cite only one example of these new concepts, quantum cryptography allows us to guarantee an absolute privacy of communications, based on the most fundamental laws of quantum mechanics.
Brief Bio
Alain Aspect, Professor of Physics at the Institut d'Optique and at École Polytechnique Palaiseau, is an experimentalist, who explores the foundations of quantum physics and their applications. He is one of the pioneers who performed seminal Bell test experiments that showed Albert Einstein’s “spooky action at a distance” with two entangled particles separated by an arbitrarily large distance. By emphasizing the extraordinary character of entanglement, Aspect's experiments are considered to have played a seminal role in the emergence of the field of quantum information.
Currently, Aspect conducts experiment on quantum degenerate ultra-cold atomic gases, mostly in quantum atom optics and quantum simulation.
Stages in his career include the École Normale Supérieure de Cachan (ENS Cachan), the Institut d'Optique and the Université d'Orsay, the Collège de France, and CNRS at Laboratoire Charles Fabry de l’Institut d'Optique. He also served as a volunteer, teaching in Yaoundé (Cameroon). He is a member of numerous scientific academies, including the French Académie des Sciences, the French Académie des Technologies, the National Academy of Sciences USA, and the Austrian Academy of Sciences. Among his many distinctions are the CNRS gold medal (France), the Humboldt award (Germany), the Tomassoni award (Italy), the Max Born Award of the Optical Society of America (USA), the Albert Einstein medal (Switzerland), the Niels Bohr gold medal (Denmark), the Wolf prize in Physics, the Balzan Prize in Quantum Information.
Slides
September 23, 2014
Andre Geim,
University of Manchester
Host:
Minn-Tsong Lin
Time: 2:20 pm -3:20 pm
Place: Room 204, CCM-New
Phys. building
Title:
Random Walk to Stockholm
Abstract
Graphene – a single plane of carbon atoms – is perhaps the simplest material one can imagine. On the other hand, graphene has acquired so many superlatives to its name that people started calling it a wonder material. I will discuss how this research started and then try to explain why graphene has attracted so much attention.
Brief Bio
Sir Andre Konstantin Geim (Fellow of the Royal Society) is a Soviet-born Dutch-British physicist working at the University of Manchester. Geim was awarded the 2010 Nobel Prize in Physics jointly with Konstantin Novoselov for his work on graphene. He is Regius Professor of Physics and Royal Society Research Professor at the Manchester Centre for Mesoscience and Nanotechnology.
He received a diploma (MSc degree equivalent) from the Moscow Institute of Physics and Technology (MIPT) in 1982 and a Candidate of Sciences (PhD equivalent) degree in metal physics in 1987 from the Institute of Solid State Physics (ISSP) at the Russian Academy of Sciences (RAS) in Chernogolovka. After earning his PhD, Geim worked as a research scientist at the Institute for Microelectronics Technology (IMT) at RAS, and from 1990 as a post-doctoral fellow at the universities of Nottingham (twice), Bath, and Copenhagen. He obtained his first tenured position in 1994, when he was appointed associate professor at Radboud University Nijmegen, where he did work on mesoscopic superconductivity. In 2001 he became a professor of physics at the University of Manchester, and was appointed director of the Manchester Centre for Mesoscience and Nanotechnology in 2002. Geim served as Langworthy Professor between 2007 and 2013, leaving this endowed professorship to Dr. Novoselov in 2012. Also, between 2007 and 2010 Geim was an Engineering and Physical Sciences Research Council (EPSRC) Senior Research Fellow before becoming one of Royal Society Research Professors. In 2010 Radboud University Nijmegen appointed him professor of innovative materials and nanoscience, extending Geim’s long list of honorary professorships.
Geim shared the 2000 Ig Nobel Prize in physics with Michael Berry for the frog experiment. In 2006 he appeared on the Scientific American 50. The Institute of Physics awarded him the 2007 Mott Medal and Prize for his discovery of a new class of materials—free-standing two-dimensional crystals—in particular graphene. In 2007 he was also elected a Fellow of the Royal Society. He shared the 2008 EuroPhysics Prize with Novoselov for discovering and isolating a single free-standing atomic layer of carbon (graphene) and elucidating its remarkable electronic properties. In 2009 he received the Korber European Science Award. The United States National Academy of Sciences honored him with the 2010 John J. Carty Award for the Advancement of Science for his experimental realization and investigation of graphene, the two-dimensional form of carbon. He was awarded one of six Royal Society 2010 Anniversary Research Professorships. The Royal Society added its 2010 Hughes Medal for his revolutionary discovery of graphene and elucidation of its remarkable properties. He was awarded honorary doctorates from Delft University of Technology, ETH Zurich, the University of Antwerp and the University of Manchester. In 2010, Geim was appointed as Knight Commander of the Order of the Netherlands Lion for his contribution to Dutch Science. Geim was furthermore made a Knight Bachelor in the 2012 New Year Honors for services to science. He was elected a foreign associate of the US National Academy of Sciences in May 2012 and awarded the Copley Medal in 2013.
On 5 October 2010, Geim was awarded the 2010 Nobel Prize in Physics jointly with Novoselov for groundbreaking experiments regarding the two-dimensional material graphene. The lecture for the award took place on 8 December 2010 at Stockholm University.
September 30, 2014
Demetri Psaltis,
Ecole Polytechnique Federale de Lausanne (EPFL)
Host:
Chia-Lung Hsieh
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Imaging with multimode fibers
Abstract
Holography and phase conjugation were proposed in the middle 1960’s for correcting the distortions in imaging systems due to aberrating or scattering media. These early methods have been revisited in recent years and successful experimental demonstrations have been reported with digital holographic methods in which the recording and reconstruction of the hologram is done with the help of a digital computer. The digital holographic methods offer a lot more flexibility and control compared to the all-optical methods of the past making holographic imaging much more practical. In addition, adaptive wavefront shaping techniques have been recently developed providing a set of related and synergistic methods for imaging in complex media. In this presentation we will focus primarily on the application of the modern tools of holography to the control of light transmission through multi-mode fibers. The modal dispersion that severely scrambles images propagating through multi-mode fibers can be compensated allowing us to exploit the many degrees of freedom available in the multi-mode fiber for imaging and sensing.
Brief Bio
Demetri Psaltis was educated at Carnegie-Mellon University where he received the Bachelor of Science degree in Electrical Engineering and Economics in 1974, the Master's in 1975, and the PhD in Electrical Engineering in 1977. In 1980, he joined the faculty at the California Institute of Technology, Pasadena, California. He served as Executive Officer for the Computation and Neural Systems department from 1992-1996. From 1996 until 1999 he was the Director of the National Science Foundation research center on Neuromorphic Systems Engineering at Caltech. He was director of the Center for Optofluidic Integration at Caltech. In the beginning of 2007, he moved to the Ecole Polytechnique Fédérale de Lausanne, Switzerland where he is professor and director of the optics laboratory and the dean of the school of engineering.
October 7, 2014
Harald Fritzsch,
Ludwig Maximilians University Munich
Host:
Wei-Shu Hou
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
The Fundamental Constants
and their Time Variation
Abstract
In the Standard Model of Particle Physics there are 28 fundamental constants. Theoretically they are not understood. I will discuss these constants, which are mostly mass parameters.
Astrophysical experiments indicate that the finestructure constant depends on time. In this case Grand Unification implies a time variation of the QCD scale. Thus the masses of the atomic nuclei and their magnetic moments will vary slowly in cosmological time.
I proposed an experiment, which is currently carried out by Prof. Haensch at the MPQ in Munich and his group. The results indicate a time dependence of the QCD scale. An astrophysics experiment at the VLT in Chile gives a similar result.
Brief Bio
Harald Fritzsch received his Diplom at University of Leipzig in 1968, and finished his Doctoral Dissertation in Theoretical Physics at Technical University of Munich in 1971. He then joined as Research Associate at CERN and Caltech, where he advanced, together with Murray Gell-Mann, the "color" gauge group of SU(3) for the strong interactions in 1972. After another term at CERN, he became Full Professor at University of Wuppertal in 1977 and University of Bern in 1978, before becoming (Sommerfeld) Chair of Theoretical Physics at University of Munich in 1980. He has made particularly important contributions to the development of quantum chromodynamics, to the theory of quark masses and mixings, and the grand unification of the Standard Model of elementary particles. He is also the author of many famous popular science books on particle physics, and the nonfiction "Escape from Leipzig".
Slides
October 14, 2014
Hao-Chung Kuo,
National Chiao Tung University
Host:
Yang-Fang Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
2014 Nobel Prize in Physics---
Light Emitting Diodes:
Innovation for Solid State Lighting
Abstract
Since Dr. Losev reported creation of the first light emitting diode (LED) in 1927, LED has been gone through near hundred of years for researches and developments. The first visible LED was developed in 1962 by Dr. Holonyak and the first high brightness blue LED was fabricated by Dr. Nakamura in 1993. Therefore, the age of solid state lighting (SSL) is coming during the explosive advancements of LEDs was introduced. In recent years, the record of light output efficiency for LEDs is unceasing broken and has been stridden forward.
On October 7, 2014, the Nobel Prize in Physics was awarded to Dr. Isamu Akasaki, Dr. Hiroshi Amano and Dr. Shuji Nakamura for "the invention of efficient blue LEDs which has enabled bright and energy-saving white light sources". They gave great breakthroughs in high brightness LED fabrication methods, started from III-nitride material expitaxy by metal organic chemical vapor deposition (MOCVD), which opening a new vision for SSL. The related growth methods, quantum physics, material sciences, and even nano technologies was performed and introduced in high brightness LED developments.
To be the next generation of light source for human beings living, it is essential to enhance the internal quantum efficiency (IQE), light extraction efficiency (LEE), and improving droop behavior for wide spread adoption of LEDs.
However, the current white light LEDs relies on rare earth doped phosphors, which suffering from the high cost of rare-earth, and the stoke energy loss by down-converting the blue emission of LEDs into green and red light. Therefore, developing phosphor-free white light LEDs that intrinsically with broad-band emission spanning across the visible spectrum is an important issue for the near future. In addition, 3D core-shell nanorods LEDs attracted a lot of attentions due to its promising applications in nano devices. Compared with planer LEDs, 3D core-shell nanorod LEDs could reach to higher active area, higher LEE and against the quantum confined Stark effect (QCSE) through the growth of non-polar/semi-polar multiple quantum wells (MQWs) on the sidewalls of core-shell structure.
This talk will give an overview on our recent progress in LEDs, including the studies of droop behavior improvements and the state-of-the-art for 3D white light LEDs, especially focusing on MOCVD growth and 3D characterization. Meanwhile, potential advantages and challenges of this new strategy will also be discussed.
Brief Bio
Hao-Chung Kuo received his Bachelor of Science in 1990 from Department of Physics, National Taiwan University, Taiwan, R.O.C.. He received his Master of Science in 1995 from Department of Electrical and Computer Engineering, Rutgers University, USA, and his Ph.D. in 1999 from Department of Electrical and Computer Engineering, University of Illinois at Urbana Champaign, USA. He has an extensive professional career spanning academia and industry, including: research consultant in Lucent Technologies, Bell Laboratories (1993–1995), and a member of technical staff in fiber-optics division at Agilent Technologies (1999–2001) and LuxNet Corporation (2001–2002). Since October 2002, he has been with the National Chiao Tung University (NCTU) as a faculty member of the Institute of Electro-Optical Engineering. He is now the distinguish professor of Department of Photonics and Institute of Electro-optical Engineering, NCTU. Professor Kuo was awarded the Institution of Engineering and Technology (IET) fellow in 2005, and the Optic Society Association (OSA) and the International Society for Optics and Photonics (SPIE) fellow in 2007. He is IEEE senior member and association editor of IEEE/OSA Journal of Lightwave Technology (JLT) and the Journal of Selected Topics in Quantum Electronics (JSTQE) special issue in solid state lighting. He received Ta-You Wu Young Scholar Award from National Science Council and Young Photonics researcher award in 2007. His current research interests include semiconductor lasers, VCSELs, visible and UV LEDs, quantum-confined optoelectronic structures, optoelectronic materials, and solar cells. He has authored and coauthored over 200 SCI journal papers, over 200 conference papers and 8 granted and 14 pending patents.
Slides
October 21, 2014
Tzay-Ming Hong,
National Tsing Hua University
Host:
Chong Der Hu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
How physicists can find ideas
in the National Palace Museum
Abstract
In March the senior editor of Physics Today wrote an extensive article reporting “Taiwan’s science miracle”. By coincidence the Physics Update column in the very same issue featured our work (Chou et al., PRL 113, 034302 (2014)) on the curling of scrolled artwork, which fun project I hope to share with you today. This phenomenon, called 起瓦 (Chi-War), is undesirable from aesthetic point of view and poses real threats to tear fiber and dislodge pigment. It has lingered for more than two thousand years and is often ascribed to factors such as environmental humidity or the glue used to affix the painting to its mounting. We demonstrate that the spontaneous extrinsic curvature incurred from the storage is in fact more essential to understanding and curing 起瓦. Experiments, theoretical model, and simulations are employed jointly to find consistent scaling behavior for the 起瓦 height. This knowledge enables us to propose modifications on the traditional mounting techniques that are tested to be effective at mitigating 起瓦. By experimenting on polymer-based films, we demonstrate the possible relevance of our study to the modern development of flexible electronic paper.
Our work is not only a fine example of the relevance of physics in culture and our daily life, but suggests that disciplines as disparate as physics and art conservation (fill in your main hunting field) should talk to each other.
Brief Bio
Prof. Hong received his Bachelor degree at NTU Physics on 1982 and Ph.D. in Physics at University of California, San Diego on 1988. He then spent two terms of postdoc in UK at the Cavendish Lab and Sheffield University, respectively. Although trained as a theorist (specialized in polymer dynamics and magnetism), he pretends to do experiments (in crumpling, arts conservation, imbibition, sonoluminescence, X-ray emission by tape-peeling, and random-close-packing). The latter hobby has been fruitful and become his main occupation. Representative work includes PRL 101, 125504 (2008); ibid. 103, 263902 (2009) issue cover; and ibid. 112, 034302 (2014) Editor's Selection with Synopsis in Physics, also featured in Science, Physics Today and New Scientist magazines.
Slides
October 28, 2014
Shean-Jen Chen,
National Cheng Kung University
Host:
Chen Yuan Dong
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Temporal Focusing-Based Multiphoton
Microscopy and Microprocessing
Abstract
A microscope based on temporal focusing offering widefield multiphoton excitation has been developed to provide fast three-dimensional (3D) biomedical imaging and microprocessing. This configuration can produce multiphoton images at a frame rate greater than 100 Hz with a lateral spatial resolution of less than 0.5 μm and an axial resolution of approximately 3.5 μm. Three techniques have been adopted to promote the spatial resolution: 1) to enhance the lateral and axial resolutions to 168 nm and 1.22 μm by using a second order nonlinear structured- illumination microscopy, 2) to further improve to 50 nm with the fast frame rate by integrating an astigmatism approach, and 3) to correct the disturbances induced from the sample and the environment via a wavefront sensorless adaptive optics system. In temporal focusing-based multiphoton microprocessing, 3D freeform polymer microstructures using rose Bengal as the photoinitiator are created by sequentially stacking two-dimensional fabricating patterns. Compared to conventional scanning multiphoton excitation and fixed mask pattern generation, this approach offers freeform microstructures and a greater than three-order increase in fabrication speed. Furthermore, the laser system can offer multiphoton-induced ablation to rapidly disrupt bio-tissues. Experimental results demonstrate that it is more efficient to achieve large-area laser ablation machining without bringing serious photothermal damages in non-machining region, and the machined volume rate can be reached to around 1.6×106 μm3/s for machining the chicken tendon.
Brief Bio
Dr. Shean-Jen Chen received his B.S. degree from National Taiwan University in 1987 and his M.S. degree in Mechanical Engineering from Columbia University in 1991. In December 1996, he was awarded his Ph.D. degree for research in adaptive noise cancellation and image restoration at the University of California, Los Angeles (UCLA). He joined the Synchrotron Radiation Research Center of Taiwan from 1998 to 2000 where he involved in the development of soft x-ray active gratings and microfocusing optical systems. Currently, he is a Distinguished Professor at the Engineering Science Department and also the Director General at Center for Micro/Nano Science & Technology of National Cheng Kung University (NCKU) of Taiwan. He is actively engaged in researching in Advanced Nonlinear Optical Microscopy and Three-dimensional Photolithography.
Slides
November 4, 2014
Masaki Oshikawa,
University of Tokyo
Host:
Ying-Jer Kao
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Symmetry-Protected Topological Phases
(and me)
Abstract
Classification of quantum phases is one of the major goals of condensed matter physics and statistical mechanics. Traditionally, the classification has been done based on spontaneous symmetry breakings and/or local order parameters. However, recently, distinct phases without any of these characteristics have been recognized as "topological phases". Symmetry-protected topological (SPT) phases are a subclass of the topological phases that are distinct only in the presence of symmetries. Although the concept of SPT phases was established following the discovery of topological insulators, an archetypal example of symmetry-protected topological phases, the Haldane phase, has been known since much earlier. I will review the early history of, as well as recent developments on, SPT phases from my personal perspective.
Brief Bio
Prof. Oshikawa received his B.S. degree from Department of Physics, University of Tokyo, then studied in Izuyama Group, Institute of Physics and Kohmoto Group, Institute for Solid State Physics to received M.S. and Ph.D. degree in University of Tokyo. In his educational life, he was also JSPS Research Fellow and Research Associate in Nagaosa Group, Department of Applied Physics, University of Tokyo. After receiving his Ph.D. degree, he spent three years as postdoc in Affleck Group, Department of Physics and Astronomy, University of British Columbia in Canada, then he became Associate Professor in Department of Physics, Tokyo Institute of Technology in 1998, and now he is Full Professor in Institute for Solid State Physics, University of Tokyo from 2006. His research interest is to solve a strongly interacting system with large number of degrees of freedom in statistical or condensed matter physics and focus on quantum many-body problems, such as quantum spin systems and low-dimensional electron systems. He received Ryogo Kubo Memorial Award (2003), SEST award for young scientist (2005), and JSPS Prize (2008).
November 12, 2014
William Phillips,
NIST
Host:
Chia-Lung Hsieh
Time: 2:20 pm -3:20 pm
Place: Dr. Poe Lecture Hall, IAMS building
Note: Special Time and Space!!!
Title:
Why condensed matter physicists
should pay attention to atomic physics
Abstract
AMO physics has been revolutionized by the advent of ultracold atomic gases, including quantum degenerate Bose and Fermi gases. Much of the activity with cold atoms brings AMO physics into close contact with Condensed Matter. Atoms in optical lattices (externally imposed periodic potentials) can mimic the behavior of electrons in crystals; Bose-Einstein condensed gases or Cooper-paired degenerate Fermi gases can mimic superfluid helium or superconducting materials; atomic gases can exhibit phase transitions that are traditionally studied in solids. These and other atomic phenomena offer possibilities for measurement and control that can be quite different from those available in materials. This talk will explore some of the current intersections of AMO and CM physics and speculate about the future of the relationship.
Brief Bio
Dr. William D. Phillips received his Ph.D. from MIT in 1976 and after two years as a Chaim Weizmann postdoctoral fellow at MIT, he joined the National Institute of Standards and Technology in 1978. He is currently the leader of the Laser Cooling and Trapping Group of NIST's Physical Measurement Laboratory, and a Distinguished University Professor at the University of Maryland. He is a Fellow of the Joint Quantum Institute, at NIST and the University of Maryland. Dr. Phillips’s research group studies the physics of ultracold atomic gases. In 1997, Dr. Phillips shared the Nobel Prize in Physics "for development of methods to cool and trap atoms with laser light."
November 25, 2014
Zvi Bern,
UCLA
Host:
Yutin Huang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Harmony of Scattering Amplitudes:
From Collider Physics to Supergravity
Abstract
Recent years have seen enormous advances in our ability to compute elementary-particle scattering amplitudes in quantum field theory. Associated with these advances are the discovery of remarkable new structures obeyed by scattering amplitudes. Examples from particle collider physics and supergravity theories will be given. In collider physics this includes new precision calculations of multi-jet process using quantum chromodynamics. Supergravity theories are shown to be remarkably well behaved in the ultraviolet as a consequence of a newly uncovered connection to gauge theories which shows that gravitons can be viewed as two copies of gluons.
Brief Bio
Zvi Bern is currently Professor of Physics at the University of California at Los Angeles. He received undergraduate degrees in physics and mathematics from the Massachusetts Institute of Technology and a PhD in theoretical physics from the University of California at Berkeley. He did postdoctoral work at the Niels Bohr Institute, Los Alamos National Laboratory, and the University of Pittsburgh before joining the UCLA physics department. He won a Sloan Foundation Fellowship and a US Department of Energy Outstanding Junior Investigator Award. He is a Fellow of the American Physical Society. He is interested in finding ever improved ways to understand how elementary particles scatter off each other, bypassing complexities inherent in Feynman diagrams. He is especially interested in applications to physics at the Large Hadron Collider at CERN and, on the more theoretical side, in applications to supersymmetric gauge and gravity theories, including their surprisingly good ultraviolet properties. In 2014, Zvi Bern has been selected to receive the American Physical Society’s (APS) J.J. Sakurai Prize for "For pathbreaking contributions to the calculation of perturbative scattering amplitudes, which led to a deeper understanding of quantum field theory and to powerful new tools for computing QCD processes". He shared the award with Lance J. Dixon of SLAC and David A. Kosower of Saclay.
December 2, 2014
Douglas N. C. Lin,
UC Santa Cruz
Host:
Yen-Ting Lin
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Ubiquity of planets and diversity of
planetary systems: Origin and Destiny
of multiple super Earths and gas giants
Abstract
Planetary astrophysics is the most rapidly advancing field in the astronomical community today. Planetary census suggest they are common and their mass-period distribution is a function of the mass and metallicity of their host stars. The diverse and intriguing kinematic properties of multiple planetary systems are likely to be the direct consequence of both the boundary condition of their natal disks and the long-term evolution of nonlinear dynamical systems. I will show how the emergence of super-Earth is a robust process whereas the formation of gas giant planets is a threshold phenomena. The topics to be discussed include physical barriers in the planet building process, the role of migration in their evolving natal disks, planets' interaction with each other and with their host stars.
I will also discuss some key observations which may provide quantitative tests for planet formation theories and new clues on the dynamical evolution and internal structure of planets.
Brief Bio
Prof. Douglas NC Lin is a world renown theoretical astrophysicist. He obtained his bachelor’s degree from McGill University in 1971, and PhD degree from Cambridge University in 1976. Since 1979 he has been faculty at UC Santa Cruz. He was also the founding director of Kavli Institute of Astronomy and Astrophysics in Beijing. Prof. Lin has made fundamental contributions to the theory of accretion disks, the formation of stars and planets. He was recipient of many distinguished awards and fellowships, including the Guggenheim fellowship, Humbolt fellowship, and Sackler distinguished fellowship.
Slides
December 9, 2014
David Jewitt,
UCLA
Host:
Yen-Ting Lin
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Comet Science
Abstract
Most comets are ice-containing bodies that have been stored in one of two distant reservoirs (the Kuiper belt and the Oort cloud) since the formation of the Solar system. I will provide an accessible, sweeping and scientifically up-to-date overview of the current understanding of comets, of their storage reservoirs, and of their importance for understanding the formation and evolution of the Solar system.
Brief Bio
David Jewitt is a professor of astronomy at the University of California, Los Angeles, husband of Chinese-American solar astronomer Jing Li and father of wayward teen Suu Suu. He studies primitive solar system bodies to help understand the origin of the solar system. Recipient of the 2012 Shaw and Kavli Prizes, he is also a member of the US National Academy of Science, the American Academy of Arts and Sciences and the Norwegian Academy of Sciences and Letters.
December 16, 2014
Cheng Chin,
University of Chicago
Host:
Yuan-Huei Chang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Observation of ferromagnetic orders
and roton excitations in a Bose gas
Abstract
Bosons have a tendency to condense in the lowest momentum state at low temperatures, a phenomena known as Bose-Einstein condensation. What will happen if there are multiple ground states sharing the same energy? Will bosons condense to a single minimum or a superposition of the two? Surprisingly, in such a system the Bose superfluid exhibits many unexpected behaviors, including a pseudospin order, leading to polarization of the entire sample or ferromagnetic domains. The excitations of the system also exhibit a roton-maxon structure associated with strong interactions in superfluid helium.
Brief Bio
Cheng Chin is a professor at the James Franck Institute, Enrico Fermi Institute, and the Department of Physics at the University of Chicago. He received his Ph.D. from Stanford University and completed his postdoc research at Innsbruck University in Austria. He conducts experimental research on ultracold atoms. He has received the Sloan Fellowship (2006), Packard Fellowship (2006), OCPA Young Research Award (2006), NSF CAREER Award (2008), IUPAP Young Scientists Prize (2008), I. I. Rabi Prize (2011) and Humboldt Fellowship (2013).
December 23, 2014
Ryu Sasaki,
Shinshu University
Host:
Pauchy Hwang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Recent Developments in Exactly Solvable
Quantum Mechanics
Abstract
After a brief review of the well known solvable potentials and the solution methods, a No-Go theorem for one-dimensional exactly solvable quantum mechanics is explained. It says, whatever new solvable systems you may find, their eigenfunctions consist of only the classical orthogonal polynomials, i. e. Hermite, Laguerre and Jacobi. Attempts to evade the No-Go theorem resulted in the discoveries of Askey-Wilson polynomials, etc in 1980's, by considering difference equations, instead of differential equations. I will focus on new developments since 2008. It started with the construction of complete sets of orthogonal polynomials starting with degree 1, as solutions of exactly solvable quantum mechanics. Now infinitely many such polynomials are constructed and known as the multi-indexed orthogonal polynomials and exceptional orthogonal polynomials.
Brief Bio
Ryu Sasaki got his B. Sc. in 1971 at Department of Physics, University of Tokyo. His Ph.D in Physics was on "Dispersion approach to Field Theory" supervised by Kazuhiko Nishijima in 1976 from University of Tokyo. He went to Europe for Post. Doc, two years in Max-Planck Institute for Physics and Astrophysics, Munich, two years in Niels Bohr Institute, Copenhagen, and one and half year in Institute of Physics, Utrecht University, the Netherlands. He got professorship at Research Institute for Theoretical Physics, Hiroshima University in 1982. He worked at Yukawa Institute, Kyoto University from 1990 to his retirement in 2013.
His research in theoretical physics ranges from non-perturbative approach to quantum field theory, soliton theory (classical and quantum), integrable systems including Toda field theory and non-linear sigma models, to exactly solvable quantum mechanics. He served as an Associate Editor of Nuclear Physics B[FS] for 18 years, an Editorial Board Member of Journal of Physics A for six years, became the Fellow of Institute of Physics (UK) in 2004. He got the Daiwa-Adrian Prize with Ed. Corrigan in 1998. Now he is staying at Department of Physics, NTU for two months for delivering the third Kroll Lectures.
Slides
December 30, 2014
Ye-Hwa Chen,
Georgia Institute Technology
Host:
Ching-Ming Wei
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
What is "Responsible Conduct of Research"?
Abstract
The number of papers retracted by scientific journals in the year of 2011 was thirteen times higher than the average number at the beginning of the century. The growth rate is alarmingly fast. If a paper is retracted, both the academic life of the authors and the reputation of the institute will be tarnished. The so-called "Responsible Conduct of Research" (RCR) is recognized as an important topic dealing with these behavior and phenomena. In this talk, I will introduce various aspects of RCR including the policy, main areas covered, and specific examples. The emphasis will be on the easily made mistakes by researchers in Taiwan and Asian countries.
Brief Bio
Ye-Hwa Chen is a professor of the George W. Woodruff School of Mechanical Engineering of Georgia Institute of Technology. He received his PhD from the University of California, Berkeley. His research and teaching interests include research ethics, control of uncertain dynamical systems, constrained mechanical systems, and intelligent systems. He received the Outstanding Paper Award from the IEEE Transactions of Fuzzy Systems of the IEEE Control System Society, Sigma Xi Best Paper Award, and Sigma Xi Junior Faculty Award.
January 6, 2014
Xiao-Gang Wen,
Massachusetts Institute of Technology
Host:
Feng-Li Lin
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
A unification of matter and information
-- a second quantum revolution
Abstract
Physics, in particular, condensed matter physics, is a very old field. Many people are thinking that the exciting time of physics has passed. We enter the beginning of the end of physics. The only important things in physics are its engineering applications, such as optical fiber and blue LED. However, I feel that we only see the end of the beginning. The exciting time is still ahead of us. In particular, now is a very exciting time in physics, like 1900 - 1930. We are seeing/making the second quantum revolution which unifies information, matter and geometry. Here I will describe the previous four revolutions in physics: mechanical revolution, electromagnetic revolution, general relativity revolution, and quantum revolution, as well as the fifth -- the second quantum revolution. Each revolution unifies seemingly unrelated phenomena. Each revolution requires new mathematics to describe the new theory. Each revolution changes our world view.
Brief Bio
Prof. Xiao-Gang Wen is a Cecil and Ida Green Professor of Physics at the Massachusetts Institute of Technology, and his expertise is in condensed matter theory in strongly correlated electronic systems. Prof. Wen studied superstring theory at Princeton University where he received his Ph.D. degree in 1987. He later switched his research field to condensed matter physics in Institute for Theoretical Physics, UC Santa Barbara from 1987 to 1989. Prof. Wen introduced the notion of topological order and quantum order, to describe a new class of matter states. This opens up a new research direction in condensed matter physics. Then he pointed out that topological order is nothing but the pattern of long range entanglements. This led to a notion of symmetry protected topological (SPT) order (short-range entangled states with symmetry) and its description by group cohomology of the symmetry group. He received Overseas Chinese Physics Association outstanding young researcher award, and is Fellow of American Physical Society and A.P. Sloan Foundation, Distinguished Moore Scholar, Caltech, and Distinguished Research Chair and Isaac Newton Chair, Perimeter Institute.
Slides
January 13, 2014
David Spergel,
Princeton University
Host:
Yen-Ting Lin
Time: 2:20 pm -3:20 pm
Place: Room 104, CCM-New
Phys. building
Title:
Planck and Beyond
Abstract
The Planck Telescope has made an accurate full-sky measurement of the cosmic microwave background (CMB) temperature, the leftover heat from the Big Bang. These measurements probe both the physics of the very early universe and the basic properties of the universe today. The Planck measurements confirm the earlier results from the WMAP telescope and rigorously test our standard cosmological model and provide an accurate determination of basic cosmological parameters (the shape of the universe, its age, and its composition). When combined with other astronomical measurements, the measurements constrain the properties of the dark energy and the nature of dark matter. The observations also directly probe the physics of first moments of the Big Bang: the current data are consistent with the idea that the early universe underwent a period of rapid expansion called inflation.
Many key cosmological questions remain unanswered: What happened during the first moments of the big bang? What is the dark energy? What were the properties of the first stars? I will discuss the role of ongoing and future CMB observations and describe how the combination of large-scale structure, supernova and CMB data can be used to address these key cosmological questions.
Brief Bio
David N. Spergel is Charles A. Young Professor of Astronomy and chair of the Department of Astrophysical Sciences at Princeton University. Dr. Spergel has made major contributions to cosmology, astroparticle physics, galactic structure, and instrumentation. He led the theoretical analysis for the Wilkinson Microwave Anisotropy Probe (WMAP), invented novel coronagraphs for planet detection, originated and explored the concept of self-interacting dark matter, and showed that the Milky Way is a barred galaxy. Spergel serves as Chair of the Space Studies Board and co-chair of the WFIRST Science Definition Team. He is a member of the National Academy of Sciences and the American Academy of Arts and Sciences. He was a MacArthur Fellow, a Shaw Laureate, and was just awarded the Heinemann Prize. Nature named Spergel as “One of the Ten Scientists Who Mattered in 2014”
Slides