ASIAA/CCMS/IAMS/LeCosPA/NTU-Phys/NTNU-Phys Joint Colloquia

March 22, 2016

 Hsiu-Hau Lin, National Tsing Hua University

Host:  Yang-Fang Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
The dawn of quantum biology

Abstract

In biology, quantum dynamics is usually regarded as irrelevant because the messy environment in living organs should destroy quantum coherence without a hitch. However, as biological processes at microscopic scale become more and more revealing in recent years, there are strong evidences that quantum dynamics is vitally important in certain biochemical reactions. I shall kick off the introduction using photosynthesis as an illustrating example. Then, I will move on to the detection mechanism of odorant molecules. That is to say, do we need a quantum nose smell? Experimental evidences, theoretical constructions and controversies will be unrolled in the talk, revealing potential breakthrough in our understanding of biological receptors at nanoscale.

Brief Bio

Prof. Lin is a theoretical physicist with research focus on biophysics, statistical physics and material sciences. He is now Tsing Hua Distinguished Professor at NTHU in Taiwan. In addition to research activities, he is devoted to physics education and participates in open education for years. Prof. Lin is the sole awardee receiving two ACE Awards of Open Education Consortium: the first one in 2013 (Thermal and Statistical Physics) and the second one in 2014 (General Physics). He is trying very hard to be a good researcher, a good teacher and a good person as well.

Slides

March 29, 2016

 Yuanbo Zhang, Fudan University

Host:  Chi-Te Liang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
New opportunities in 2D materials

Abstract

Two-dimensional (2D) atomic crystals, best exemplified by graphene, have emerged as a new class of material that may impact future science and technology. The reduced dimensionality in these 2D crystals often leads to novel material properties that are vastly different from that in the bulk. We refer to such a recurring scheme as “less is different”. In this talk I will illustrate this scheme with two 2D materials that we found particularly interesting – black phosphorus and 1T-TaS2. These two layered materials have vastly different properties. Black phosphorus is a 2D semiconductor, and its superior material quality has recently enabled us to observe the quantum Hall effect. 1T-TaS2, on the other hand, is a metal with a rich set of charge density wave phases. We explore their electronic properties while the doping and dimensionality of the 2D systems are modulated.

Brief Bio

Prof. YuanboZhang received his BS from Peking University in 2000 and his PhD in Physics from Columbia University in 2006. He was a Miller Research Fellow at the University of California at Berkeley from September 2006 to June 2009, a postdoc research associate at IBM Almaden Research Center from March 2010 to September 2010, and a professor of Fudan University from 2011. His main research interests are: Electronic transport in low-dimensional systems; Scanning probe techniques and their application in studying low-dimensional nanostructures. Major honors include: Charles Townes Fellowship, Columbia University (2005); Miller Fellow, University of California, Berkeley (2006); IUPAP Young Scientist Prize, International Union of Pure and Applied Physics (2010); Qiu Shi Outstanding Young Scholar Award, Qiu Shi Foundation (2013); Nishina Asia Award, Nishina Memorial Foundation, Japan (2014).

Slides

April 12, 2016

 Tai-Huang Huang, Academia Sinica

Host:  Tsyryan Yu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Nuclear Magnetic Resonance (NMR) From Basic Physics to Biomedical Applications

Abstract

Nuclear Magnetic Resonance (NMR) is, arguably, the most versatile and powerful physical technique applicable in a wide range of scientific disciplines ranging from physics, chemistry, biology, material science, to medicine. It began with the discovery of nuclear spin, the demonstration of nuclear magnetic resonance phenomenon, and the development of NMR theory in the first half of the 20th century by physicists. NMR quickly become an indispensable tool for chemists in the 1960s when it was discovered that chemical structure affects nuclear spin resonance frequency. With the availability of superconducting magnet, high power computers, and the development of multi-dimensional techniques in the 1970s NMR became a major tool for probing macromolecular structure, dynamics and function. In the 1980s, magnetic resonance imaging (MRI) was developed and subsequently it became one of the most important imaging modality in hospitals. In this talk I will give a broad overview of the field and its future perspectives. I will also give some examples on its biomedical applications with results mainly from my own laboratory.

Brief Bio

Prof. Tai-Huang Huang received his BS from National Taiwan Normal University in 1969 and he obtained PhD in Physics from Brandeis University in 1979. He was affiliated in several prestigious institute such as, M.I.T. and University of Cambridge. Presently he is a Distinguished Research Fellow at Institute of Biomedical Sciences, Academia Sinica. His research area covers Biophysics, Structural Biology and NMR Spectroscopy in Solution and in Solid

Slides

April 19, 2016

 Eberhard K. U. Gross, Max Planck Institute

Host:  Guang-Yu Guo
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
How to make the Born-Oppenheimer approximation exact: A fresh look at potential energy surfaces and Berry phases

Abstract

The Born-Oppenheimer approximation is among the most fundamental ingredients of modern Theoretical Chemistry and Condensed-Matter Physics. This approximation not only makes calculations feasible, it also provides us with an intuitive picture of chemical reactions. Yet it is an approximation, and some of the most fascinating phenomena occur in the regime where the Born-Oppenheimer approximation breaks down. Prime examples are the process of vision, photovoltaic processes as well as phonon-driven superconductivity. To tackle such situations where strong non-adiabatic couplings dominate the scene, one has to face the full Hamiltonian of the complete system of electrons and nuclei. We deduce an exact factorization of the complete electron-nuclear wavefunction into a purely nuclear part and a many-electron wavefunction which parametrically depends on the nuclear configuration and which has the meaning of a conditional probability amplitude. From this we derive equations of motion for the nuclear and electronic wavefunctions which lead to a unique definition of exact potential energy surfaces as well as exact geometric phases [1]. We discuss a case where the exact Berry phase vanishes although there is a non-trivial Berry phase for the same system in Born-Oppenheimer approximation, implying that in this particular case the Born-Oppenheimer Berry phase is an artifact which has no counterpart in the true electron-nuclear wave function. [2] Furthermore, whenever there is a splitting of the exact nuclear wavepacket in the vicinity of an avoided crossing, the exact time-dependent surface shows a nearly discontinuous step [3], reminiscent of Tully surface hopping algorithms. Based on this observation we propose novel mixed-quantum-classical algorithms [4]. [1] A. Abedi, N.T. Maitra, E.K.U. Gross, Phys. Rev. Lett. 105, 123002 (2010). [2] S.K. Min, A. Abedi, K.S. Kim, E.K.U. Gross, Phys. Rev. Lett. 113, 263004 (2014). [3] A. Abedi, F. Agostini,Y. Suzuki, E.K.U. Gross, Phys. Rev. Lett. 110, 263001 (2013). [4] S.K. Min, F. Agostini, E.K.U. Gross, Phys. Rev. Lett. 115, 073001 (2015).

Brief Bio

Eberhard Gross completed his doctorate in physics at J. W. Goethe University Frankfurt in 1980. After postdoctoral fellowships at J. W. Goethe University and UC Santa Barbara, he joined the University of Würzburg as a Fiebiger Professor in 1990. He became an elected Max Planck Fellow and Professor of Theoretical Physics at the Free University Berlin in 2001. Since 2009, he has been a Director at the Max Planck Institute of Microstructure Physics in Halle. The research interests of Eberhard Gross span superconductivity, magnetism, quantum transport as well as how these phenomena evolve in real time under the influence of external fields. He layed the foundation of time-dependent density functional theory with a statement now known as Runge-Gross theorem. This theorem demonstrates that the intricate dynamics of an interacting many-electron system can be described and understood by knowledge of the time-dependent density alone. In recent years his research interests included the coupled motion of electrons and nuclei beyond the Born-Oppenheimer approximation. He has published over 240 articles and book chapters which have been cited more than 23000 times.

Slides

April 26, 2016

 Bing Sheu, National Chiao Tung University

Host:  Yang-Fang Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
For Young Generation to Versatilely Adapt in Digital Era
數位時代的孫悟空

Abstract

In 21st Century, smart digital devices and intelligent digital machines/systems have significantly out-performed human beings in many known tasks. Recent examples include AlphaGo system from Google DeepMind Project beating human expert player. This talk in Physics Department Colloquium addresses the issues about what young people can master in order to find suitable role in man-machine symbiotic society for the next several decades.
在21世紀數位時代，年輕人與智能機器的角色已經黃金交叉了。如果執行相同的工作，人類的效率遠遜於機器人、不堪一擊。我們以宏觀的視野、跳脫出框架，有 效地協助年輕的聽眾來建立適合自己的價值觀與思想體系。做一位數位時代的孫悟空，彈性、機智、有能力處理新冒出來的挑戰，達到多贏的快樂境界。 本演講是三部曲的首部：人機共存的「基本法則」(ground rules)，善用幾千年累積的高級智慧，這是根的部分。接著的第二部曲會是：年輕人如何掌握、以及趨吉避凶？這是莖的部分。然後第三部曲將是：人與資訊 攜手，共同迎接光明的未來，這是葉與花的部分。

Brief Bio

Honorary / Chair Professorship, awarded by National Chiao Tung University, National Taiwan University of Science & Technology, National Taipei University of Technology, National Taipei University, National I-Lan University, Chang Gung University, plus in process by National Sun Yat-Sen University (pending).
1978年以優異成績畢業於台大電機系、並且獲得滿貫的七次書卷獎, 1996年「國際電機電子學會」會士 IEEE Fellow, 總編輯，IEEE「超大型積體電路系統期刊」(SCI), 創刊總編輯，IEEE「多媒體期刊」(SCI), 「線路與系統學術會」(IEEE Circuits and Systems Society) 總裁, 2006年教育部第一屆「教育奉獻獎」。 經歷：美國南加州大學正教授(1985-1998)，矽谷軟體公司(1999-2006)，新竹科學園區(2006-Oct. 2015) 榮譽/講座教授： 交通大學、臺灣科技大學、臺北科技大學、臺北大學、宜蘭大學、長庚大學， 加上中山大學(2016 pending) 。

Slides

May 3, 2016

 Jing-Tang Yang, National Taiwan University

Host:  Yang-Fang Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Flight dynamics of insects in free flight

Abstract

Flying with low wing beats, erratic trajectory, and broad wings, the flight motion of butterfly is unique and very different from that of other insect. The dancing-liked flight motion of the butterfly can be contributed to two reasons; unsteady flight speed and significant rotation of body. These two phenomena, however, were often neglected and scarcely examined in previous studies. In this talk, we are going to reveal the flight features of butterflies and damselflies, which are regarded as two of the better models for MAVs.
We first recorded the flight motion of butterflies (Kallima inachus) in forward flight freely. A three-dimensional numerical model of a butterfly is then created to study the butterflies in transient flight based on the experimental data. The fluid domain is solved with the commercial software (FLUENT), a finite volume base solver. To achieve the butterfly in transient flight, two-way fluid structure interaction is applied. The aerodynamic force acting on the butterfly is integrated around the butterfly surface, by which the flight speed and the center mass of butterfly are updated in each tine step. The butterfly in this model is allowed translating freely in both vertical and horizontal directions, which is similar to the butterfly in free flight.
We investigate how the body posture affects the butterfly flight. Body motion in a simulation is prescribed and tested with varied initial body angle and rotational amplitude. From the flight trajectories, butterflies tend to fly vertically with vertical body and high rotation amplitude, and tend to fly horizontally with low body angle and rotation amplitude. The analysis reveals that the rotation of body motion helps the butterflies to control the direction of the vortex rings generated, and further affects their flight modes. In engineering perspective, to create the flight vehicle with lower wing beat as butterflies is easier and more achievable. The inspiration of flight controlled with body motion from the flight of a butterfly might yield an alternative way to control future micro flight vehicles.

Brief Bio

Professor Yang received his Ph.D. degree in 1983 from the Energy Division of the Mechanical Engineering Department of the University of Wisconsin at Madison and became a professor of the Department of Mechanical Engineering at National Taiwan University in August, 2008. He had been the faculty of the Department of Power Mechanical Engineering at National Tsing Hua University during 1983-2008. The core of his multidisciplinary research is fluid mechanics. Current research topics contain energy and green engineering, microfluidics and lab-on-a-chip, biomimetic engineering and biophysics, jet propulsion, and laser diagnostics.

May 10, 2016

 Pisin Chen, LeCosPA

Host:  Yang-Fang Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Black Hole Information Loss Paradox
             – The War Continues to Rage –

Abstract

The question of whether Hawking evaporation violates unitarity, and therefore results in the loss of information, remains unresolved since Hawking's seminal discovery 40 years ago. If Hawking radiation does not carry any information out from the ever-shrinking black hole, it seems that unitarity, a fundamental assumption in quantum mechanics and quantum field theory, is violated once the black hole completely evaporates. On the other hand, attempts to recover information via quantum entanglement lead to the firewall controversy. In this talk, we will first introduce the essence of the black hole information loss paradox. Then we will review various proposed solutions to the paradox with their pros and cons. Attention will be given to the cases of black hole remnant and the firewall proposals. In particular, we argue that, if the firewall is located near where the horizon would have been, based on the spacetime evolution up to that time, later quantum fluctuations of the Hawking emission rate can cause the ``teleological'' event horizon to have migrated to the inside of the firewall location, rendering the firewall naked. This casts doubt about the notion that firewalls are the “most conservative” solution to the information loss paradox. Last but not least, we suggest that this raging black hole war may hopefully be settled experimentally through “accelerating plasma mirrors” using advanced laser and nano-fabrication technologies.

Brief Bio

Pisin Chen received his Bachelor’s Degree from NTU Physics in 1972 and PhD from UCLA in theoretical particle physics under J. J. Sakurai. He joined NTU Department of Physics and Graduate Institute of Astrophysics as a professor in 2007. He holds the NTU C.C. Leung Chair Professor of Cosmology and has been the founding Director of Leung Center for Cosmology and Particle Astrophysics (LeCosPA) since 2007. He initiated the founding of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University and SLAC in 2000, and has been its Permanent Member. He was elected Fellow of American Physical Society in 1994. He is two-time recipient of the Gravity Research Foundation Annual Essay Competition Awards (3rd Prize, 2002; 4th Prize, 1995). He is internationally recognized for contributions in plasma physics, particle beam physics, particle astrophysics, cosmology, gravity and black hole physics. Trained as a theoretical physicist, he developed a strong interest in experimentation since 1990s. He initiated the Askaryan Radio Array (ARA) cosmic neutrino observatory in 2009 and serves as its International Co-Spokesperson. ARA is ROC’s first major scientific project at the South Pole. Another project, the Ultra-Fast Flash Observatory (UFFO), to observe the prompt signals of gamma ray bursts (GRB) within 1-2 seconds, was successfully launched by Russia on April 28, 2016.

Slides

May 17, 2016

  Juhn-Jong Lin, National Chiao Tung University

Host:  Ming-Wen Chu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
The Kondo effect:
spin and orbital degrees of freedom

Abstract

The Kondo effect is a long-standing paradigmatic many-body problem in condensed matter physics. The recent progresses in nanoscience and technology has further made possible new realizations of exotic Kondo physics. In this talk, I will discuss some experimental aspects of (1) the standard Kondo effect due to the existence of isolated localized spin-half magnetic moments, and (2) the two-impurity Kondo effect featured quantum critical behaviors of the transport properties. Lastly, (3) I will discuss our observation of nonmagnetic Kondo effect due to two-level tunneling systems. In the last case, the Kondo physics originates from the coupling of the electronic orbital wave-functions with dynamical structural defects.

Brief Bio

Professor Juhn-Jong Lin obtained his BS degree from National Chiao Tung University (NCTU) in 1979. He obtained his PhD degree from Purdue University (USA) in 1986. He was an associate professor and a professor in the Department of Physics at National Taiwan University from 1988 to 1997. He joined the Institute of Physics at NCTU in 1997. His research efforts focus on low temperature physics, mesoscopic physics, nanoscale physics, and disordered electronic systems.

May 18, 2016

  Chung-Pei Ma , University of California

Host:  Yuan-Huei Chang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Supermassive Black Holes at
the Centers of Galaxies

Abstract

Black holes are among the most fascinating astrophysical objects and have long entranced the public. I will describe recent progress in discovering black holes beyond one billion solar masses lurking at the centers of massive elliptical galaxies in the local universe. These massive black holes are plausible descendants of luminous quasars in the young universe and inform us of how cosmic structures evolved over the past 10 billion years. Merging black hole binaries in this mass range are also the primary sources of gravity waves in the nano-Hertz range targeted by ongoing pulsar timing array experiments.

Brief Bio

Chung-Pei Ma is a Professor of Astronomy at the University of California, Berkeley. She received both her undergraduate and Ph.D. degrees in physics from the Massachusetts Institute of Technology and has served as the cosmology Scientific Editor for the Astrophysical Journal. Her research interests span the properties of dark matter and dark energy, the cosmic microwave background, galaxy formation and evolution, supermassive black holes, and the large-scale structure of the universe.

May 24, 2016

 Shawn-Yu Lin, Rensselaer Polytechnic Institute

Host:  Yuan-Huei Chang
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
3D Photonic Crystal: Light Trapping, Anomalous Refraction and Non-Planckian Thermal Radiation

Abstract

The field of photonic-crystals has become one of the most influential and wide-ranging realms of contemporary electro-magnetism and optics. In this talk, I will describe two recent advances in 3D photonic-crystal operating in optical wavelengths. The first is a striking discovery of non-Planckian thermal emission in a 3D metallic photonic-crystal. The second is the first observation of acutely-negative-refraction in a 3D silicon photonic-crystal for light trapping, guiding and near-unity solar absorption.

Brief Bio

In 1992, he joined IBM T.J. Watson research center, first working on wave-function symmetry of high temperature superconductors and then on ultra-fast photo-conductive switches. In 1994, Dr. Lin joined DOE-Sandia National Laboratories and led its efforts in developing photonic-crystal devices for communication, defense and energy applications. In 2004, Dr. Lin was appointed as a chair professor at the Future-Chips Constellation and Physics Department of Rensselaer Polytechnic Institute. Dr. Lin’s current research interest is in active photonic-crystals for light trapping, non-equilibrium thermal radiation, sensing, lighting and thin-film solar cell architectures.

May 31, 2016

 David L. Meier, California Institute of Technology

Host:  Keiichi Umetsu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
Black Holes: The Ultimate Engines

Abstract

For nearly a century some of the most important astrophysical systems have been described in terms of every-day models or paradigms. For example, stellar interiors are likened to furnaces and the Big Bang is likened to an explosion. In the case of active galaxies and quasars, early observers, who studied the emission lines and ultraviolet continuum of these objects, often referred to the “central engine” that powered their energy output (often as great as 10^40 Watts or higher). We now are reasonably certain that, in each such active galaxy, the central object that is responsible for the “engine” is a supermassive black hole (as large as 20 billion solar masses), which is accreting gas and stars from the galaxy in which it resides.
In fact, as more is learned about how an accreting black hole can produce the different types of behavior seen in active galaxies, the more accurate the Engine Paradigm appears to be. A black hole engine has most of the major subsystems that are in a standard automobile internal combustion engine and can be throttled from a quiet idle to an explosive roar. This includes an engine block (the black hole), a fuel supply (actually two types of fuel), a carburetion/fuel-injection system that converts gaseous fuel into a fine mist, a combustion chamber where the internal (gravitational) energy of the fuel is released, and five different exhaust systems to carry the spent fuel away from the combustion chamber. Black hole engines also produce enormous amounts of mechanical energy, which can be used to assist in the explosion of some stars, help trigger star formation in certain cases, and even shut off star formation in an entire galaxy.
In this talk I will discuss the inner workings of black hole engines of different sizes and the important roles black holes play in the evolution of stars and galaxies.

Brief Bio

Dr. David Meier received his PhD from the University of Texas at Austin in 1977, working with three different advisors during his tenure. His three research topics were (1) developing a theory of magnetohydrodynamic jets in collapsing supernova cores (David Schramm), (2) predicting the appearance of primeval galaxies (which are now known as Lyman Break Galaxies; Beatrice Tinsley), and (3) developing the theory and predicting the appearance of radiation-driven winds from super-Eddington accretion disks around black holes (J. Craig Wheeler).
He continued these lines of research as a postdoc at Caltech in Kip Thorne’s group and as a NATO Postdoctoral Fellow at the University of Cambridge in Martin Rees’s group.
In 1980 he was hired onto the staff at Caltech’s Jet Propulsion Laboratory, where he also began to work in observing and engineering projects, including astronomical interferometric imaging (Southern Hemisphere VLBI, the Japanese VSOP and Russian RadioAstron space radio VLBI missions, and the optical Space Interferometry Mission [SIM]), as well as the development of parallel algorithms for space and astrophysical computations on the new parallel Hypercube supercomputers being developed at JPL. With other Caltech colleagues he performed some of the first simulations of magnetized jets in the 1980s and has continued this work with Masanori Nakamura in the past 15 years, during which time he also developed a fully general-relativistic generalized Ohms law as well as advanced numerical techniques for evolving both the gravitational and electromagnetic fields simultaneously during black hole formation. He is the author of over 230 publications, 90 of which are refereed, and has published articles in Scientific American, Nature and Science magazines, and the Springer book “Black Hole Astrophysics: The Engine Paradigm”.
He currently is retired from JPL, but still has a position on the Caltech staff and works with Marshall Cohen and other colleagues around the world on theoretical interpretation of radio VLBI observations of jets ejected from black holes.

June 7, 2016

 Way-Faung Pong, Tamkang University

Host:  Ming-Wen Chu
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
The Correlations and Dynamics of Spins in an Spin Glass System (Mn0.6Ni0.4)TiO3

Abstract

Neutron scattering studies have been proved to be a powerful tool to study the static and dynamic magnetic correlations in the spin-glass state of several systems [1,2]. Recently, an XY-like spin-glass system (Mn1-xNix)TiO3 for 0.40 ≤ x ≤ 0.48 has been reported to show linear magnetoelectric (ME) coupling [3, 4] and striking memory effects [5]. In this work, we have carried out neutron scattering experiments on the single crystals of (Mn0.6Ni0.4)TiO3 (hereafter MNTO40) to investigate the correlations and dynamics of spins in the XY-like spin-glass state of NMTO40. Neutron powder diffraction experiments suggest the presence of a broad peak at finite Q≈ 0.67 Å-1 below the spin-glass temperature (TSG) . The strong diffuse scattering is the signature of short range antiferromagnetic spin correlations. We have also carried out elastic and inelastic neutron scattering studies on the single crystal around (0, 0, 1.5) reciprocal lattice point to study short range antiferromagnetic correlations. Elastic neutron scattering experiments have shown that magnetic diffuse scattering intensity starts to increase around 12 K which is close to the TSG. Inelastic neutron scattering (QENS) results show the presence of quasielastic magnetic scattering profiles below TSG. The life time of dynamic correlations, τ~ ћ/ΓL, obtained from the full width at half maximums (FWHMs) (ΓL) of QENS profiles are about 1.71 and 2.52 psec at 9 K along [0, 0, 1.52] and [0.01, 0.01, 1.50] directions. These experimental findings reveal that the short-range ordered antiferromagnetic clusters with short-lived spin correlations exist in the spin-glass state of NMTO40 below TSG.
[1] J. S. Gardner et al., Phys. Rev. Lett. 83, 211 (1999).
[2] W. Bao et al., Phys. Rev. Lett. 91, 127005 (2003).
[3] Y. Yamaguchi et al., Phys. Rev. Lett. 108, 057203 (2012).
[4] Y. Yamaguchi et al., Nat. Comm. 4, 2063 (2013).
[5] S. Chi et al., Phys. Rev. B 90, 144429 (2014).

Brief Bio

Prof. Pong received the Bachelor degree in Physics from National Central University in 1980, Taiwan and received the Ph.D. degree in Physics from University of Notre Dame in Indiana, US in 1990. Then, he joined Tamkang University in Tamsui, Taiwan as a faculty member in the Department of Physics, where his research was focused on the use of synchrotron-radiation related techniques for probing the atomic, electronic structures and magnetic properties of condensed matters. Specifically, his group is involved with using x-ray absorption spectroscopy (XAS), x-ray emission spectroscopy (XES)/resonant inelastic x-ray scattering (RIXS), x-ray magnetic circular dichroism (XMCD) and scanning transmission x-ray microscopy (STXM) to study the semiconducting and magnetic alloys, transitional-metal oxides. His personal interests largely involve fundamental problems in solid-state physics, but there are often technologically applications as well. He was promoted to be a professor since August 1997 and was the chairman of Department of Physics during 1998-2002. His current research interests focus on the structures of low-dimensional nanomaterials (carbon nanotubes, graphene, graphene oxides, Co/Mg-doped ZnO nanorods/quantum dots etc.), magnetic alloys, charge density wave, multiferroic and highly correlated electron systems.
Prof. Pong has contributed over one-hundred seventy publications in peer-reviewed journals. In addition, he has also contributed over fifty scientific presentations on his research to professional conferences, universities and research institutions during his tenure at Tamkang University.

June 14, 2016

 Kuei-Hsien Chen, Academia Sinica

Host:  Yang-Fang Chen
Time: 2:20 pm -3:20 pm
Place: Room 104, CCMS-New Phys. building
Title:
The Search for the
Next-generation Thermoelectric Materials

Abstract

Discovered nearly 200 years ago by Seebeck, thermoelectric effect converts heat into electricity. It is followed by Peltier who used electricity for cooling. Nowadays, both thermoelectric (TE) and Peltier effect have been implemented in applications such as Radioisotope thermoelectric generator (RITEG) in the satellite Voyager and low-noise cooling system for high sensitivity detectors, respectively. However, they’re limited to niche applications due to the high cost of the TE devices. Therefore, much room remains for improvement in efficiency and cost reduction to make thermoelectric a viable candidate for the recovery of wasted heat in our daily life. This presentation will cover the milestones in thermoelectric research, the recent works by the Academia Sinica-NTU team. A perspective of future thermoelectricity will also be addressed.

Brief Bio

Dr. Kuei-Hsien Chen (陳貴賢) obtained his BS degree from Electrical Engineering, NTU and his MS and Ph.D. degrees from Applied Science, Harvard University in 1989. He worked on CVD diamond synthesis at General Electric R&D Center till 1992 before he joined the Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica in 1993. He is currently the Distinguished Research Fellow and academic deputy director of IAMS, and adjunct research fellow in the Center for Condensed Matter Sciences (CCMS) in NTU. He works on the synthesis and applications of advanced materials, particularly their energy applications including electrocatalysis, photovoltaic, thermoelectricity, and solar fuels. Dr. Chen has published more than 400 papers and holds 12 patents with more than 10500 citations and an h-index of 52.