September 11, 2017
Kang
L. Wang , UCLA
Host:
Yuan-Huei
Chang
Time: 2:20 pm -3:20 pm
Place: Room 204, CCMS-New Phys. building
Title:
Quantized
Signature of Majorana Fermion: Particle being its own Anti-particle
Abstract
In 1937, Ettore Majorana proposed a particle being its antiparticle.
Since its inception, Majorana has been under intensive pursuit both
theoretically and in experiments. Recent interest in robust
topologically protected quantum computing has accelerated the
experimental quest of Majorana. Among various proposals, I will discuss
the scenario when a topological insulator meets a superconductor. This
system offers a possible host for Majorana.
The talk will begin from the experimental efforts of the quest of
dissipationless transport: quantum Hall without magnetic field, quantum
spin Hall to quantum anomalous Hall (QAH). The latter was enabled by a
long term effort in the materials growth of topological insulator -
magnetic (Cr) doped BiSbTe to achieve reliably QAH. The recent work of
topological insulator (TI) has led to the recognition of the importance
of topology phase in condensed matters by the 2016 Nobel Prize in
Physics. I will discuss the topological transitions of Dirac electrons
for TI in QAH. When the QAH edge states interface with a
superconductor, the Dirac electron space is transformed to the Nambu
space, hosting Majorana fermions via pairing energy. We will describe
our experimental efforts to show the convincing evidence of quantized
signature of the one-dimensional chiral Majorana fermion [1]. A
half-integer quantized conductance plateau (0.5 e2/h) gives a firm
signature of the elusive Majorana fermion for the first time by
scanning topological phase transitions under the reversal of the
magnetization. This finding gives a new direction for new topological
quantum computing.
Reference[1]. Science, July 21, 2017
Brief Bio
Dr. Kang L. Wang is currently Distinguished Professor and the Raytheon
Chair Professor in Physical Science and Electronics in the University
of California, Los Angeles (UCLA). He is affiliated with the
Departments of ECE, MSE and Physics. He received his BS degree from
National Cheng Kung University (Taiwan) and his MS and PhD degrees from
the Massachusetts Institute of Technology. He is a Member of Academia
Sinica, Fellow of the IEEE, and a member of the American Physical
Society. He was a Guggenheim Fellow. He also served as Editor-in-Chief
of IEEE TNANO, editor of Artech House, Consulting Editor for Spins, and
Associate Editor for Science Advances. His research areas include
nanoscale physics and materials; topological insulators; molecular beam
epitaxy; spintronics and low dissipation devices; neurodynamics and
neurotronics.
September 19, 2017
Din-Ping
Tsai, NTU-physics
Host:
Yuan-Huei
Chang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Plasmonic Metasurface
for
Photonics Application in Demand
Abstract
The functionalities of traditional optical component are mainly based
on the phase accumulation through the propagation length, leading to a
bulky optical component such as lens and waveplate. Plasmonic
metasurfaces composed of artificial structures have attracted a huge
number of interests due to their ability on controlling the optical
properties including electromagnetic phase as well as amplitude at a
subwavelength scale [1]. They therefore pave a promising way for the
development of flat optical devices and integrated optoelectronic
systems. In this talk, several research topics for photonic
applications based on metasurfaces will be performed and discussed:
Beam deflection [2], highly dimensional holographic imaging [3],
versatile polarization generation and analysis [4], multi-functional
and tunable metadevices [5], achromatic metasurface devices [6] and
engineering non-radiating anapole mode in free space [7].
Reference
[1] N. Yu, and F. Capasso, Nat. Mater. 13, 139-150 (2014).
[2] S. Sun, et. al., Nano Lett. 12, 6223-6229 (2012).
[3] Y.-W. Huang, et. al., Nano Lett. 15, 3122-3127 (2015).
[4] P. C. Wu, et. al., Nano Lett. 17, 445-452 (2017).
[5] Y.-W. Huang, et. al., Nano Lett. 16, 5319-5325 (2016).
[6] S. M. Wang, P. C. Wu, et. al., Nature Commun. 8, 187 (2017).
[7] P. C. Wu, et. al., under review.
Brief Bio
Din Ping Tsai received Ph.D in Physics from University of Cincinnati,
USA in 1990. He worked at Micro Lithography Inc., California, USA;
Ontario Laser and Lightwave Research Center, Toronto, Canada; and
National Chung Cheng University, Taiwan from 1990 to 1999. He joined
Department of Physics, National Taiwan University as an Associate
Professor in 1999, and became Professor and Distinguished Professor in
2001 and 2006, respectively.
He served as the Director General of the Instrument Technology Research
Center (NARL) located in Hsinchu Science Park, Taiwan from 2008 to
2012. He is the Director and Distinguished Research Fellow of Research
Center for Applied Sciences, Academia Sinica since 2012. He is a Fellow
of AAAS, APS, IEEE, OSA, SPIE, TPS and Electro Magnetics Academy. He is
also Academician of Asia Pacific Academy of Materials and Corresponding
Member of International Academy of Engineering.
He currently serves as Editor of Progress in Quantum Electronics,
Associate Editor of Journal of Lightwave Technology, Member of
Editorial boards of Physical Review Applied, Optics Communications,
Plasmonics, ACS photonics, and Optoelectronics Letters, respectively.
He is now the President of Taiwan Information Storage Association. He
was the Director of the Board of SPIE and Committee Member of IEEE/LEOS
Nanophotonics; OSA Fellows & Honorary Members; SPIE Fellow;
IEEE Joseph F. Keithley Award; OSA and IS&T Edwin H. Land
Medal; respectively. He was also President of Taiwan Photonics Society;
Chairman of IEEE Instrument and Measurement Society Taipei Chapter; and
Chairman of the SPIE Taiwan chapter.
September 26,
2017
Ing-Shouh
Hwang
,
IoP AS
Host:
Ming-Wen
Chu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Low-Voltage Coherent
Electron Imaging
Based on a Single-Atom Electron Source
Abstract
Imaging of two-dimensional materials and low-atomic-number materials
has been one of the most intensively studied subjects in electron
microscopy. It has been a general trend to develop low-voltage electron
microscopes due to their high imaging contrast of the sample and low
radiation damage. Atom-resolved TEM images with operation voltages as
low as 15 to 40 kV have been demonstrated in recent years due to
advancement in aberration correction techniques. However, such
techniques become extremely challenging and complicated as the
operating voltage reaches levels lower than 10 kV. Electron beams with
energy from 500 eV to 10 keV have not been demonstrated to achieve
atomic resolution. In this talk, I will discuss new schemes based on
highly coherent single-atom electron sources.
Over the past several years, we have been developing low-voltage
(805000 V) coherent electron imaging techniques. An advantage of this
approach is that there is a possibility to achieve diffraction-limited
resolution without the need to fabricate a high-quality lens. Coherent
diffractive imaging has been successfully demonstrated in optical
microscopy and x-ray microscopy. There are relatively fewer experiments
in electron microscopy mainly because optical lasers and synchrotron
light sources are usually with better coherence than electron sources.
Now we have demonstrated full spatial coherence for single-atom
electron sources. Thus coherent imaging based on single-atom electron
sources is very promising to reach atomic resolution even for
non-periodic structures like biological molecules. Our ultimate goal is
to achieve high-contrast and high-spatial-resolution imaging of
two-dimensional materials and organic molecules under low-dose
conditions.
Brief Bio
EDUCATION
1993 Ph.D Applied Physics, Division of Applied Science, Harvard
University
1984 B.S. Department of Electrical Engineering, National Taiwan
University, Taiwan
EXPERIENCE
2005 Adjunct Professor, Department of Material Sciences and
Engineering, NTHU
2000 Research Fellow, Institute of Physics, Academia Sinica
2000 Adjunct Associate Professor, Department of Physics, NTHU
1998 Associate Research Fellow, Institute of Physics, Academia Sinica.
1994 Assistant Research Fellow, Institute of Physics, Academia Sinica
1993 Postdoctoral Fellow, Applied Physics, Harvard University
AWARD
2006 Outstanding Nano-tech Research Award, Taiwan Nanotechnology
Industry
Development Association.
2000 Outstanding Research Award, National Science Council.
1999 Young Investigator Award, Academia Sinica.
RESEARCH INTERESTS
surface and interface sciences, scanning probe microscopy, electron/ion
beam techniques, development of new instrumentation techniques
October 03, 2017
Howard E. Haber ,
UCSC
Host:
Xiao-Gang
He
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Does the Higgs boson signal
the end
of particle physics?
Abstract
The Higgs boson was initially proposed in 1964 and was finally
discovered at the Large Hadron Collider (LHC) in 2012. With the Higgs
boson discovery, the Standard Model of Particle Physics is now
complete. But, does this signal the end of discoveries in particle
physics? In this talk, I shall first discuss why the Higgs boson was an
essential ingredient of the Standard Model. I will then review the
current experimental status of the Higgs boson and future prospects for
precision studies of its properties. Finally, I will explain why new
physics beyond the Standard Model must exist and whether evidence for
such new phenomena is likely to emerge at the LHC and/or the next
generation of collider facilities.
Brief Bio
EDUCATION AND EXPERIENCE
∙ B.S. and M.S. – MIT-physics, 1973
∙ Ph.D. – University of Michigan-physics, 1978
∙ Postdoc – Lawrence Berkeley Laboratory, 1978-1980
University of Pennsylvania, 1980-1982
University of California, Santa Cruz,1982-1985
∙ Member of the faculty at UC Santa Cruz since 1985
∙ Department of Energy Outstanding Junior Investigator, 1985-1988
∙ Elected Fellow of the American Physical Society, 1993
∙ Trustee of the Aspen Center for Physics, 2005-2011
∙ Member of the Particle Data Group since 2007
AWARDS
∙ Alexander von Humboldt Research Award, 2009
∙ Honorary designation of Distinguished Professor of Physics at UC
Santa Cruz, 2015
∙ Co-recipient of the American Physical Society J.J. Sakurai Prize in
Theoretical Physics,
2017
Streaming and Video
October 17, 2017
Misao
Sasaki,
Kyoto University
Host:
Yu-Tin
Huang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Inflationary Universe,
Primordial Black Holes and Gravitational Waves
Abstract
Inflation has become an integrated part of the standard cosmology
thanks to recent progress in cosmological observations. However, there
still remain many unknowns about inflation. In this talk, I mention a
few interesting observational results that may be primordial signals
from inflation. In particular, I advocate an idea that the recently
detected black hole binaries are primordial in their origin, and the
rapidly developing field of gravitational wave astronomy/astrophysics
may provide clues about the nature of inflation.
Brief Bio
Academic Degrees
1976 Bachelor of Science, Department of Physics, Kyoto University
1978 Master of Science, Department of Physics, Kyoto University
1981 Doctor of Science, Department of Physics, Kyoto University
Academic Career
1986 Assistant professor, Department of Physics, Kyoto University
1990 Associate professor, Research Institute for Theoretical Physics,
Hiroshima University
1991 Associate professor, Yukawa Institute for Theoretical Physics,
Kyoto University
1995 Professor, Department of Earth and Space Science, Osaka University
2003 Professor, Yukawa Institute for Theoretical Physics, Kyoto
University
2008 KIAS Scholar, Korea Institute for Advanced Study
2013 Director, Yukawa Institute for Theoretical Physics, Kyoto
University
Academic Awards
1997 Chushiro Hayashi Prize, the Astronomical Society of Japan (with
Hideo Kodama)
1997 Ronbun-Sho (Prize for Seminal Papers), the Physical Society of
Japan (with Takahiro Tanaka, Kazuhiro Yamamoto and Jun’ichi Yokoyama)
2008 Humboldt Research Award, Alexander von Humboldt Foundation
2010 Daiwa Adrian Prize, the Daiwa Anglo-Japanese Foundation (with
David Wands et al.)
2011 Honorary Professor, Tomsk State Pedagogical University
October 24, 2017
Clifford
Chao, CMU
Host:
Yuan-
Huei Chang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Evolution in Technology and
Clinical
Application of Particle Therapy
Abstract
Not Available
Brief Bio
KS Clifford Chao is a pre-eminent expert in the use of image-guided
targeted radiotherapy for the treatment of cancers and has served as
Principle Investigator of multiple NIH and DoD research grants and
published more than 180 peer-reviewed papers. He was a tenured
associate professor at Washington University School of Medicine in St.
Louis, a professor at University of Texas, MDACC, and later became
distinguished chaired Professor and the Department Chair of Radiation
Oncology of Columbia University and Weill Cornell Medical College.
Dr. Chao’s research focus includes combining positron emission
tomography (PET) and computed tomography (CT) images to construct
individualized treatment plans that address the molecular
characteristics of each tumor. He co-founded two MD Anderson-based
start-up company using a knowledge-based artificial intelligence to
guide high precision robotic image-guided therapy system that helps map
the exact location of a tumor and direct radiation towards the
malignant cells while avoiding healthy tissue.
October 31, 2017
Gerhard
Wagner ,
Harvard
Medical School
Host:
Tsyr-Yan
Yu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Molecular Mechanisms of
Cancer
and Structure-derived Translational
Opportunities
Abstract
In this talk, Prof. Wagner will introduce his early works as a
physicist in developing NMR spectroscopy methods for protein
characterization. He will then introduce the first step in protein
translation, which is called translation initiation. Translation
initiation is the process of assembly of elongation-competent 80S
ribosomes, in which the proper start position on the mRNA is
identified. The eukaryotic translation initiation apparatus is now a
complex machinery comprising at least eleven factors. Through many
years of work, Wagner group has mapped out how these factors are
interacting with each other. In addition, Wagner group has also
identified the potential druggable targets for cancer treatment.
Brief Bio
Prof. Gerhard Wagner is Elkan Rogers Blout Professor of Biological
Chemistry and Molecular Pharmacology at Harvard Medical School. Prof.
Wagner was elected to be a member of the American Academy of Arts and
Sciences and German National Academy to honor his contribution in
developing NMR methods for protein characterization.
He received his diploma in department of physics of Technical
University and PhD from department of biophysics in ETH. He started his
independent career at University of Michigan in 1987 and was promoted
to be a full professor in 1989. He then moved to Harvard in 1990. He
has been Elkan Rogers Blout Professor since 1992.
November 07, 2017
Sandip Pakvasa
,
University
of Hawaii
Host:
Xiao-Gang
He
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
The Stern-Gerlach experiment
and
the Discovery(?) of the Electron Spin
Abstract
I will describe the story of how Stern and Gerlach set out to detect
"space quantization" of Bohr orbits and ended up discovering the spin
of the electron (3 years BEFORE the invention of spin) and how it took
five years to disentangle the muddle. I will also discuss briefly the
vexing story of a possible Stern-Gerlach experiment for free electrons.
I will note in passing the remarkably creative career of Otto Stern,
often (justifiably) called the founding father of Experimental Atomic
Physics.
Brief Bio
Professor Sandip Pakvasa graduated with a Ph. D. degree in Physics from
Purdue University in 1966. He worked at Syracuse University in 1965 to
1967 as a research associate. In 1967 he joined the University of
Hawaii as an associate Physics and became a full professor in 1974.
Professor Pakvasa has made many important contributions in particle
physics, in particular in the areas of CP violation, flavor physics in
various hadron and lepton systems, neutrino physics, cosmic rays and
particle astrophysics. He was elected a Fellow of American Physical
Society in 1976 and awarded Japan Society for Promotion of Science
Fellowship in1981 and 1985. In 2009 he was awarded University of Hawaii
Regents Medal for Excellence in Research. He received an Alexander von
Humboldt Research Award for 2013-15.
November 14, 2017
Ulf-G.
Meißner
, University
of Bonn
and
Forschungszentrum Jülich
Host:
Jiunn-Wei
Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Nuclear Physics as Precision
Science
Abstract
Theoretical Nuclear Physics has entered a new era. Using the powerful
machinery of chiral effective
Lagrangians, the forces between two, three and four nucleons can now be
calculated with
unprecedented precision and with reliable uncertainties. Furthermore,
Monte Carlo methods
can be adopted to serve as a new and powerful approach to exactly solve
nuclear structure and
reactions. I discuss the foundations of these new methods and provide a
variety of intriguing
examples. Variations of the fundamental constants of Nature can also be
investigated and the
consequences for the element generation in the Big Bang and in stars
are considered. This
sheds new light on our anthropic view of the Universe.
Brief Bio
Prof. Ulf-G. Meißner received his diploma from Ruhr-Universität Bochum,
Germany and his PhD from SUNY, Stony Brook, USA. He holds the Chair in
Theoretical Nuclear Physics at Bonn University and was the Dean of the
Faculty of Natural Sciences and Mathematics for 8 years. He is also the
Director at the Institut für Kernphysik and the Director at the
Institute for Advanced Simulation at the Forschungszentrum Jülich,
Germany.
Prof. Meißner is the author of more than 700 scientific papers with
more than 33 thousand citations and an h index of 88. He is a Fellow
of the American Physical Society and a member of The Academy of Europe.
He is the recipient of the Lise Meitner Prize of 2016 from the European
Physical Society for “his developments and applications of effective
field theories in hadron and nuclear physics, that allowed for
systematic and precise investigations of the structure and dynamics of
nucleons and nuclei based on Quantum Chromodynamics.”
November 21, 2017
Wei-Tou
Ni
,
NTHU-Physics
Host:
Cheng-Wei
Chiang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
A Brief History of
Gravitational-wave
Research and the Gravitational-wave
Spectrum
Abstract
In 1916 Einstein proposed the existence of gravitational waves (GWs)
and derived the quadrupole formula in general relativity. This
prediction eventually received observational support from the binary
pulsar after a long controversy about the existence of GWs. On the
direct experimental detection side, Joseph Weber started more than
fifty years ago. In 1966, his bar for GW detection reached a strain
sensitivity of a few times 10^−16, bridging 10 orders of magnitudes of
the sensitivity gap between GW sources and technological sensitivities
at 1916.
After proposals of cryogenic resonant detection, Weiss proposed
km-sized interferometric detectors in 1972. The response to build
interferometric detectors was then prevailing. When Advanced LIGO first
reached a strain sensitivity of the order of 10^−22, with the aid of
templates generated by numerical relativity, LIGO Science Collaboration
and Virgo Collaboration did make the first detections in their O1 Run
of aLIGO: two 5-σ GW events and one likely event. With the recent
announcements of 3-detector detection of Black Hole Binary and Neutron
Star Binary, Multi-Messenger Astronomy arose as a bright field.
Besides Earth-based GW detectors, the drag-free sensitivity of the LISA
Pathfinder has already reached to the LISA goal level, paving the road
for space GW detectors. Over the whole GW spectrum (from aHz to THz)
there are efforts for detection, notably the very-low-frequency band
(pulsar timing array [PTA], 300 pHz–100 nHz) and the extremely-low
(Hubble)-frequency band (cosmic microwave background [CMB] experiment,
0.1 aHz–10 fHz). In conclusion, we will focus some attention to
middle-frequency band and discuss AMIGO.
Brief Bio
Education and Experience:
∙B.S.–National Taiwan University-physics, 1966
∙Ph.D.–California Institute of Technology-physics and mathematics, 1972
∙Postdoc–Montana State University, 1972-1974
Member of the faculty and Honorary Chair Professor Emeritus at
National Tsing Hua University since 1974
Publications:
∙Over 200 papers, articles and book chapters
∙Over 100 SCI papers with over 2000 SCI citations
∙H-index of SCI citations is 24; 7 Physical Review Letters (5 first
author letters; 2 second author letters)
∙For last 3 years, over 20 SCI papers including 2 Astrophysical J
papers
and 3 Physics Letters A papers
Related Recent Papers:
∙K. Kuroda, W.-T. Ni and W.-P. Pan, "Gravitational waves:
classification, methods of detection, sensitivities, and sources,” Int.
J. Mod. Phys. D 24, 1530031 (44 pages) (2015).
∙W.-T. Ni, "Gravitational wave detection in space", Int. J. Mod. Phys.
D
25, 1630001 (52 pages) (2016).
∙W.-T. Ni, "Solar-system tests of the relativistic gravity", Int. J.
Mod. Phys. D 25, 1630003 (36 pages) (2016).
∙W.-T. Ni, S. Han, T. Jin, "Precision requirements and innovative
manufacturing for ultrahigh precision laser interferometry of GW
astronomy", Proc. SPIE 10023, 100230F (12 pages, November 24, 2016),
arXiv:1610.03565.
∙C.-M. Chen, J. M. Nester, W.-T. Ni, "A brief history of GW research",
Chin. J. Phys. 55, 142–169 (2017), 1610.08803.
∙A. Di Virgilio, J. Belfi, W.-T. Ni, N. Beverini, G. Carelli, E.
Maccioni and A. Porzio, "GINGER: A feasibility study," Eur. Phys. J.
Plus 132, 157 (12 pages) (2017).
Recent Book:
∙W.-T. Ni (Editor) One Hundred Years of General Relativity: From
Genesis
and Empirical Foundations to Gravitational Waves, Cosmology and Quantum
Gravity, Vol. I & II (over 1300 pages), World Scientific,
Singapore, 2017.
∙A brief history of gravitational-wave research and the
gravitational-wave spectrum
Slides
November 28, 2017
Gabriele
Veneziano ,
CERN
& Collège de France
Host:
Jiwoo,
Nam
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys.
building
Title:
A Quantum Universe
before
the Big Bang(s)?
Abstract
The fundamental role of quantum physics in modern cosmology entails a
deep revision of our traditional ideas about the Big Bang and the
beginning of time.
Brief Bio
Gabriele is an Italian theoretical physicist and one of the pioneers of
string theory. He has conducted most of his scientific activities at
CERN in Geneva, Switzerland, and he has held the Chair of Elementary
Particles, Gravitation and Cosmology at the Collège de France in Paris,
from 2004 to 2013.
Higher Education:
Undergraduate Physics, University of Florence, 1960-1965
Laurea (M.A.) in Physics, University of Florence, 1965
Graduate Studies in Physics, Weizmann Institute of Science, Rehovot,
Israel, 1966-1967
Ph.D. in Physics, Weizmann Institute, 1967
Professional Career:
Research Associate, MIT, Cambridge, Ma, USA, 1968-1969
Visiting Assistant Professor, MIT, 1969-1970
Visiting Associate Professor, MIT, 1970-1972
Full Professor, Weizmann Institute, Israel, 1971-1975
Amos-de Shalit Professor of Physics, Weizmann Institute, Israel,
1975-1977
Junior Staff Member, CERN, Geneva, 1977-1978
Senior Staff Member, CERN, Geneva, 1978-2007
Chair Condorcet, Ecole Normale Superieure, Paris, 1994
Head of Theory Division, CERN, Geneva, 1994-1997
Chair Blaise Pascal, Université Paris Sud and IHES, 2000-2002
Professor Emeritus CERN, Geneva, from 2007
Professor at Collége de France, Paris, from 2004
Professor Emeritus at Collége de France, Paris, from 2013
Global Distinguished Professor, NYU, New York, 2012-2014
Sackler Professor by special appointment, Tel Aviv University, from 2014
Cattedra Enrico Fermi, Università Roma La Sapienza, 2015-2016
Prizes and honors:
Ya. Pomeranchuk Prize, ITEP, Moscow, May 1999
Gold medal of Italian Republic, Rome, June2000
Dannie Heineman prize of American Physical Society, May 2004
Enrico Fermi prize of the Italian Physical Society, September 2005
Einstein Medal of the Albert-Einstein Gesellschaft, Berne, June 2006
Commendatore dell’Ordine al Merito della Repubblica Italiana, Rome,
Jan. 2007
Oskar Klein Memorial Medal, Stockholm, June 2007
James Joyce award, Literary and Historical Society, Dublin, Ireland,
July 2008
Tomassoni prize and medal of the University of Rome La Sapienza, Rome,
Italy, June 2009
Dirac Medal, ICTP, Trieste, Italy, November 2014
Honorary Doctorate (DSc) at Swansea University Wales, UK, January 2015
Friedel-Volterra joint prize of the Italian and French Physical
Societies, Paris 2017
December 05, 2017
Frank
H. Shu, Academia Sinica
(Academician),
Host:
Keiichi
Umetsu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Sixty Years of Spiral
Density Wave Theory
Abstract
The theory of spiral density waves had its origin approximately six
decades ago in an attempt to reconcile the winding dilemma of material
spiral arms in flattened disk galaxies. Our review begins with the
earliest calculations of linear and nonlinear spiral density waves in
disk galaxies, in which the hypothesis of quasi-stationary spiral
structure (QSSS) plays a central role. The earliest success was the
prediction of the nonlinear compression of the interstellar medium and
its embedded magnetic field; the earliest failure, seemingly, was not
detecting color gradients associated with the migration of OB stars
whose formation is triggered downstream from the spiral shock front.
The reasons for this apparent failure are understood with an update on
the current status of the problem of OB star formation, including its
relationship to the feathering substructure of galactic spiral arms.
Infrared images can show two-armed, grand design spirals, even when the
optical and UV images show flocculent structures. We suggest how the
nonlinear response of the interstellar gas, coupled with overlapping
subharmonic resonances, might introduce chaotic behavior in the
dynamics of the interstellar medium and Population I objects, even
though the underlying forces to which they are subject are regular.
We
then move to a discussion of resonantly forced spiral density waves in
a planetary ring and their relationship to the ideas of disk
truncation, and the shepherding of narrow rings by satellites orbiting
nearby. The back reaction of the rings on the satellites led to the
prediction of planet migration in protoplanetary disks, which has had
widespread application in the exploding data sets concerning hot
Jupiters and extrasolar planetary systems. We then return to the issue
of global normal modes in the stellar disk of spiral galaxies and its
relationship to the QSSS hypothesis, where the central theoretical
concepts involve waves with negative and positive surface densities of
energy and angular momentum in the regions interior and exterior,
respectively, to the corotation circle; the consequent transmission and
overreflection of propagating spiral density waves incident on the
corotation circle; and the role of feedback from the central regions.
Lastly, we discuss how the amplitude modulation predicted for the
destructive interference of oppositely propagating waves that form
standing wave patterns may have been observed in deep infrared images
of nearby spiral galaxies. We also present without comment the
tantalizing ALMA image of spiral structure in the protoplanetary disk
around the forming star Elias 2-27.
Brief Bio
Dr. Frank H. Shu is a University Professor Emeritus of University of
California at Berkeley and San Diego, a member of the US National
Academy of Sciences, the American Philosophical Society, a Fellow of
the American Academy of Arts and Sciences, a Distinguished Research
Fellow Emeritus at Academia Sinica, Taiwan, and a Senior Fellow in the
Institute for Advanced Study at City U, Hong Kong.
As one of the world's leading authorities in theoretical astrophysics
and star formation, Dr. Shu has made paradigm-shifting contributions to
human’s understanding of how astronomical structures such as stars and
spiral galaxies form. His pioneering work on the origins of stars over
a span of 30 years has generated a comprehensive and widely accepted
theory that explains the main events in the birth and evolution of a
star from the collapse of a cloud of molecules, to the accretion of a
magnetized disk of material from which planets form, to the appearance
of jets and other outflows from young stellar objects. His textbook,
The Physical Universe: An Introduction to Astronomy, has been widely
used by both undergraduate and graduate students for 30 years.
In recognition of his outstanding lifetime contributions in
theoretical astrophysics, in 2009 he was awarded the Shaw Prize in
Astronomy. His other awards include the 2009 Catherine Wolfe Bruce Gold
Medal from the Astronomical Society of the Pacific and the 2008
Centennial Medal from the Graduate School of Arts and Sciences at
Harvard University. He was also the President of the American
Astronomical Society (AAS). In addition, the main-belt asteroid 18238
Frankshu is named after him. In 2017, he was awarded an Honorary
Doctorate of Science by Stony Brook University for his research on
spiral density waves, the formation of stars and planetary systems, and
the origin of chondritic meteorites.
Dr. Shu was born in Kunming, China and came to the United States
at the age of six. He received his BS in Physics at MIT and his Ph.D.
in Astronomy at Harvard University. After a 5-year stint at the State
University of New York, Stony Brook, he joined the faculty of
University of California at Berkeley, and served as Chair of the
Astronomy Department from 1984 until 1988. He was appointed as
University Professor in 1998, an honor bestowed on only 35 faculty
members in the UC system since its founding. From 2002 to 2006 he
served as President of National Tsing Hua University in Taiwan. He then
joined the faculty of the Physics Department at the University of
California at San Diego. In 2009 he retired as University Professor and
accepted a position as a member of the Science and Technology Advisory
Group and Advisor on Energy to the Premier of Taiwan. He also Chairs
the Advisory Committee of the Green Energy Laboratory of the Industrial
Technology Research Institute (ITRI) and is a member of ITRI’s Advanced
Research Advisory Committee. From 2009 to 2015, he devoted all his
efforts at Academia Sinica and at ITRI to developing alternative
sources of energy to replace the burning of fossil fuels in response to
the growing crisis of global climate change.
In his personal research on molten salt technologies with
applications to nuclear energy, biofuels, and municipal waste
management, he has active collaborations with academic research groups
at UC Berkeley, the University of Michigan, the Ohio State University,
and City University of Hong Kong. In addition to ITRI, his industrial
partners include SGL Carbon LLC, in St. Marys, Pennsylvania. In 2016 he
formed a company Astron Solutions Corporation to bring his research
group’s inventions in molten salt technology to industrial scale to
help mitigate the problems brought on by climate change.
December 19, 2017
Naoya Shibata,
The University of Tokyo
Host:
Ming-Wen
Chu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Direct Electromagnetic Field
Imaging
by Atomic-Resolution Scanning
Transmission Electron Microscopy
Abstract
Abstract:
Scanning transmission electron microscopy (STEM) boosted by
aberration-correction technology has made it possible to directly image
atoms at localized volumes of many materials and devices especially at
interface regions where very interesting properties emerges. In STEM
imaging, a very finely focused electron probe is scanned across the
specimen and the transmitted and/or scattered electrons at each raster
position are detected by the post-specimen detector(s) to form images.
STEM image contrast is known to be strongly dependent on the detector
geometries, and in turn we gain flexibility in determining the contrast
characteristics of the STEM images by controlling the detector
geometry. By elaborating special detector geometries, we can not only
image atomic structures of materials, but also can image local
electromagnetic fields inside materials through differential phase
contrast (DPC) imaging techniques [1]. We have been continuously
developing area detectors that are capable of atomic-resolution STEM
imaging. By applying these area detectors, atomic-resolution DPC STEM
imaging has been realized [2,3].
We found that DPC STEM imaging is very powerful to directly
characterize many interesting internal electromagnetic structures such
as pn junctions in semiconductor devices [4], polar oxide interfaces
and magnetic Skyrmions [5] which cannot be observed by normal STEM
imaging techniques using annular type detectors. In addition, new STEM
development will be shown in the presentation.
[1] N. Shibata et al., Acc. Chem. Res., 50, 1502-1512 (2017).
[2] N. Shibata et al., Nature Phys., 8, 611-615 (2012).
[3] N. Shibata et al., Nature Comm. 8, 15631 (2017).
[4] N. Shibata et al., Sci. Rep., 5, 10040 (2015).
[5] T. Matsumoto et al., Sci. Adv. 2, e1501280 (2016)
Brief Bio
Dr. Naoya Shibata received a PhD in Materials Science in 2003 at
University of Tokyo. He was a JSPS Research Fellow at Oak Ridge
National Laboratory (2003-2004). He was a Research Associate in
Institute of Engineering Innovation at the University of Tokyo
(2004-2007) and was an Assistant Professor (2007-2011) and an Associate
Professor (2011-2017) and now is a Professor in the University of
Tokyo. His research focuses on the development of new imaging
techniques in scanning transmission electron microscopy and their
application to grain boundaries and interfaces in oxide materials
December 19, 2017
Gary
Shiu ,
University of
Wisconsin-Madison
Host:
Pei-Ming
Ho
Time: 3:30 pm -4:30 pm
Place: Room 104, CCMS-New Phys. building
Title:
String Theory and Cosmology
Abstract
String theory and cosmology are made for each other. Fundamental
questions about our universe call for an understanding of quantum
gravity.
On the other hand, observational cosmology provides a promising window
to probe high energy physics. In this talk, I will discuss how quantum
gravity can impose fundamental constraints on inflationary cosmology. I
will also argue why an inflationary universe -- our current theoretical
paradigm of the macroscopic world -- is incomplete on its own and
requires a microscopic, high energy completion. I will describe some
recent developments in constructing inflationary models from string
theory, the observational signatures of these models, and how one may
use data to uncover the underlying fundamental physics.
Brief Bio
Prof. Gary Shiu received his PhD degree in Physics from Cornell
University in 1998. He has held research appointments at the C.N. Yang
Institute for Theoretical Physics at Stony Brook, and the University of
Pennsylvania before joining the faculty of the University of Wisconsin,
Madison where he is currently Kellett Professor of Physics.
Prof. Shiu‘s research interests span a wide range of areas in
string theory, high energy physics, and cosmology, with an emphasis on
connecting fundamental theory to experiments.
Among the honors he received include the Guggenheim Fellowship, the
Cottrell Scholar Award, the Research Corporation Innovation Award, and
the National Science Foundation Career Award. He was also named a Kavli
Frontiers Fellow by the US National Academy of Sciences, and a Vilas
Faculty Associate. He has held visiting professorships at Stanford
University, the Perimeter Institute for Theoretical Physics, and the
Institute for Advanced Study, Princeton. He was appointed the Johannes
Diderik van der Waals Chair at the University of Amsterdam in 2012,
Chair Professor of Physics at the Hong Kong University of Science and
Technology in 2012, and Qian-Ren Visiting Professor at the University
of Chinese Academy of Sciences in 2014. He is a Fellow of the American
Physical Society, a Fellow of the Institute of Physics, and a Fellow of
the Association for the Advancement of Science.
Research achievements and scientific leadership aside, Prof. Shiu is an
award-winning teacher, and has received unreserved commendations for
his inspiring and innovative teaching approach. He received the
Chancellor’s Distinguished Teaching Award in 2012, the highest teaching
honor bestowed upon the University of Wisconsin faculty. Prof. Shiu is
passionate about taking science to students and the public.
December 26, 2017
Cheng
Chin,
The University of
Chicago
Host:
Yuan-Huei
Chang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Inflation Dynamics of
Quantum Phase
Transition in a Driven Bose-Einstein Condensate
Abstract
Quantum phase transitions are transitions between distinct many-body
ground states, and are of extensive interest in research ranging from
condensed matter physics to cosmology. Key features of the phase
transitions include a stage with rapid growth of new order parameter,
called inflation in cosmology, followed by the formation of topological
defects.
Based on Bose-Einstein condensates of cesium atoms in a shaken lattice,
we report the observation of Kibble-Zurek scaling of quantum critical
dynamics [1], and inflationary dynamics across the quantum critical
point [2]. In particular, the inflation manifests in the exponential
growth and high harmonic generations of populations in well-resolved
momentum states [3].
[1] Universal space-time scaling symmetry in the dynamics of bosons
across a quantum phase transition, Logan W. Clark, Lei Feng, Cheng
Chin, Science 354, 606 (2016).
[2] Coherent inflationary dynamics for Bose-Einstein condensates
crossing a quantum critical point, Lei Feng, Logan W. Clark, Anita Gaj,
Cheng Chin, Nature Physics (2017).
[3] Logan W. Clark, Anita Gaj, Lei Feng, Cheng Chin, Collective
emission of matter-wave jets from driven Bose-Einstein condensates,
Nature 551, 356 (2017).
Brief Bio
Education
1995-2001 Ph.D., Physics, Stanford University (Advisor: Steven Chu)
1990-1993 B.S., Physics, National Taiwan University
Academic Position
2015 JILA Visiting Fellow, JILA
2014, 2015 Visiting Professor, Universität München, Munich, Germany
2014, 2015 Guest Scientist, Max-Planck-Institut für Quantenoptik,
Garching, Germany
2014, 2015 Visiting Professor, Universität Ulm, Ulm, Germany
2014 Visiting Professor, ETH Zurich, Zurich, Switzerland
2013 Visiting Scientist, Institute of Atomic and Molecular Sciences,
Taiwan
2013 Visiting Scientist, Center for Ultracold Atoms, MIT
2013 Visiting Professor, Physics and Astronomy Department, Rice
University
2013- Professor, Enrico Fermi institute, University of Chicago
2013- Professor, James Franck institute, University of Chicago
2013- Professor, Department of Physics, University of Chicago
2009-2012 Associate Professor, James Franck institute, University of
Chicago
2009-2012 Associate Professor, Department of Physics, University of
Chicago
2005-2008 Assistant Professor, James Franck institute, University of
Chicago
2005-2008 Assistant Professor, Department of Physics, University of
Chicago
2005 Visiting Professor, ETH, Zurich, Switzerland
2003 Visiting Professor, Institut für Experimentalphysik, Universtät
Innsbruck, Austria
2003-2005 Visiting Scientist, Institut für Experimentalphysik,
Universtät Innsbruck, Austria
2001-2003 Postdoctoral Fellow, Physics Department, Stanford University
Honors and Awards (since 2003)
2017 Bose-Einstein Condensation Award
2014 American Physical Society Fellow
2014 Thomson Reuters Highly Cited Researcher
2014 Distinguished Alumni Award, Physics Department, National Taiwan
University
2013-2015 Alexander von Humboldt Research Fellow
2011 I. I. Rabi Prize, American Physics Society
2009 Materials Computation Center Travel Award
2008 IUPAP Young Scientist Prize in Atomic, Molecular and Optical
Physics
2008-2012 National Science Foundation CAREER award
2006-2012 The David and Lucile Packard Fellow
2006 Outstanding Young Researcher Award, Overseas Chinese Physics
Association
2006-2008 Alfred P. Sloan Research Fellow
2003-2005 Lise-Meitner Postdoctoral Research Fellow, Austrian Science
Fund
Academic Activities (since 2001)
2017 AMO Physics program organizer, OCPA9
2016-2019 APS DAMOP Executive Committee
2015-2019 Bose-Einstein Condensation Scientific Committee
2015 Co-organizer, INT Program: “Frontiers on Quantum Simulation with
Cold Atoms”
2014 JILA National Science Foundation Physics Frontier Center Advisory
Committee
2012 Chair, American Physical Society (APS) Midwest Prairie Section
2011~2014 Program Committee, American Physical Society Division of
Atomic, Molecular and Optical Physics (APS DAMOP) conference
2011 Co-organizer, Aspen Workshop “Few- & Many-Body Physics in
Cold Quantum Gases Near Resonances”
2011 National Science Foundation AMO Physics Proposal Review Panelist
2010 Co-organizer, Conference on Novel Quantum States in Condensed
Matter, Beijing, China
2010~2017 Editor, New Journal of Physics
2008~2017 Organizer, S.M.A.R.T. (Science, Mathematics, and Research
Training) Woodlawn High School Science Outreach Program
2008 Organizer, “Frontier in Laser Cooling, Single-Molecule Biophysics
and Energy Science – Dr. Steven Chu’s 60th Birthday Celebration
Symposium”
2007~2012 Director, Chicago MRSEC Research Experiences for
Undergraduates (REU) Program
2007, 2011 Organizer, France-Chicago research exchange program in
Physics
2005, 2009 Organizer, MidWest Regional Meeting on Quantum Gases
2001 Local committee member and Editor, the 15th ICOLS (International
Conference of Laser Spectroscopy Conference)
January 02, 2018
Michael Ramsey-Musolf,
Umass
Amherst
Host:
Xiao-Gang
He
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Fundamental Symmetries of
the
Early Universe and the Origin of Matter
Abstract
Explaining why the universe contains more matter than antimatter
remains an open problem at the interface of particle and nuclear
physics with cosmology. While the Standard Model of particle physics
cannot provide an explanation, various candidates for physics beyond
the Standard Model may do so by breaking fundamental symmetries. Among
the most interesting and testable scenarios are those that would have
generated the matter-antimatter asymmetry roughly 10 picoseconds after
the Big Bang. I discuss recent theoretical ideas for such scenarios,
developments in computing their dynamics, and prospects for testing
their viability with experiments at the high energy and high intensity
frontiers.
Brief Bio
Michael Ramsey-Musolf is a professor of physics at the University of
Massachusetts Amherst and Director of the Amherst Center for
Fundamental Interactions. He received his Ph.D. from Princeton
University, completed a post-doctoral appointment at MIT, and held
faculty positions at several universities. His research focuses on the
origin of the matter-antimatter asymmetry, physics beyond the Standard
Model of particle physics, and tests of fundamental symmetries. He is a
Fellow of the American Physical Society.