SPring 2024 Schedule
Feb. 27, 2024 ( Week 02)
You-Sheng Li
Department of Physics, National Taiwan University
Tuning Quantum Materials: Uniaxial Stressed Sr₂RuO₄ as an Example
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
Many unconventional superconductors show a similar phase diagram with different ground states, which can be tuned by external parameters, such as chemical doping or pressure. Recently, uniaxial stress, a directional probe, has shown the capabilities of tuning the electronic structures of Sr₂RuO₄ across a Van Hove singularity (VHS) [1, 2]. In this talk I will take Sr₂RuO₄ as an example to demonstrate versatility of the uniaxial stress technique. I will present thermodynamic probes I have been developed and discuss our main findings [3, 4]. In short, the phase diagram of Sr₂RuO₄, remaining unknown for more than two decades, has a SC dome in proximity to a magnetic phase like many unconventional superconductors. In addition, a strong reversal of the ECE around the VHS upon entering the SC state is observed. Together with theoretical calculations, these results strongly suggest a node-less gap opening at the VHS and, thus, place a strong constraint on possible SC order parameters.
[1] A. Steppke et al. Science 355, eaaf9398 (2017).
[2] V. Sunko et al. npj Quant. Mat. 4, 2397–4648 (2019).
[3] Y.-S. Li et al. Nature 607, 276–280 (2022).
[4] Y.-S. Li et al. Proc. Natl. Acad. Sci. USA 118, e2020492118 (2021).
Brief Bio
Dr. You-Sheng Li earned his B.S. and M.S. from National Tsing Hua University in 2006 and 2009. He received his Ph.D. from University of St Andrews (UK) in 2018. He then conducted postdoctoral research at Universität Würzburg, Germany in 2019 and Max Planck Institute for Chemical Physics of Solids, Germany from 2020 to 20203. In 2024, he joined Department of Physics at National Taiwan University as an assistant professor.
Mar. 05, 2024 ( Week 03)
Yueh-Nan Chen
Department of Physics, National Cheng Kung University
Temporal quantum correlations in the cloud
📹
Host: Hsi-Sheng Goan
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
Quantum steering is a pivotal correlation in quantum information theory. It
allows one party (Alice) to remotely steer another party (Bob) by her choice of
measurements. Not only many experimental realizations of quantum steering
have been demonstrated, but also various theoretical applications, such as
quantum foundations and one-sided device independent quantum information
tasks are proposed. Apart from the spatial quantum steering, a temporal
analogue of quantum steering was also developed recently. In this talk, I will
introduce the theory of temporal quantum steering and describe its role
among various temporal quantum correlations. By using the cloud quantum
computers, such as IBMQ and IonQ, I will further illustrate the applications of
the quantum correlations, including benchmarking quantum state transfer, the
enhanced quantum metrology, and quick charging of quantum battery.
Brief Bio
Prof. Yueh-Nan Chen is the first director of QFort. He received his
Ph.D. degree at National Chiao-Tung University in 2001. He is now
a distinguished professor of Department of Physics at National
Cheng-Kung University. His expertise ranges from quantum
transport, quantum information to quantum biology. Due to his
contributions on quantum information science, he also received
several awards, including NCTS young Theorist Award, K. T. Li
Research Award, Ta-You Wu Memorial Award, CTCI Outstanding
Physics Research Award (2020) and MOST Outstanding Research
Award (2021).
Mar. 12, 2024 ( Week 04)
Wen-Chen Chang
Institute of Physics, Academia Sinica
How well do we understand the proton?
📹
Host: Kai-Feng Chen
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
The proton is a spin-1/2 fundamental particle, discovered as a basic
constituent of atomic nuclei by Rutherford in 1917. It and its isospin
partner, neutron, carry the majority of visible mass in our universe.
Starting from Gell-Mann's quark model, the substructures of protons have
been explored mostly by the deep-inelastic scattering and Drell-Yan
process for more than five decades. In this talk, I will focus on what we
learn about the partonic structures of the proton, and how its mass and
spin can be understood by their interesting dynamics resulting from the
strong interaction. The physics results of ongoing experiments and
Taiwan's participation in the future U.S. Electron-Ion Collider will be
introduced.
Brief Bio
1990 B.S. NTU, Physics
1997 Ph.D. SUNY Stony Brook, Physics
1997-1999 Postdoctoral fellow, UC Riverside
1999-present Institute of Physics, Academia Sinica
Assitant research fellow (1999-2004)
Associate research fellow (2004-2015)
Research fellow (2015-)
2021 Fellow of Taiwan Physical Society
Mar. 19, 2024 ( Week 05)
Anne Dutrey
Laboratoire d'Astrophysique de Bordeaux
From protoplanetary Disks to Planet Formation
Host: Chian-Chou Chen
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
Understanding planet formation is a major challenge in modern astrophysics. Planets form in protoplanetary
disks orbiting around young stars. These disks are gas and dust residuals inherited from the parent clouds which form
stars. It is only recently, with the advent of large mm/submm arrays such as ALMA (Atacama Large Millimeter Array,
Chile) and its precursors, in particular the IRAM (Institute of Radio Astronomy Millimetric) array (France), that
this field has slowly emerged in the early nineties. In this talk, I will present how our understanding on planet
formation has evolved in the last 30 years. For this purpose, after an introduction describing the context, I will
focus on the observations and analyses of two emblematic objects: the young low-mass triple system GG Tauri and the
young single HAe (2.4 Msun) star AB Auriga. Starting from unresolved images of their protoplanetary disks 30 years ago,
I will show how we are now beginning to unveil their nascent planetary systems.
Brief Bio
Anne Dutrey is a worldwide recognized expert in mm/submm interferometry and pioneer in studying the gaseous and dusty
protoplanetary disks properties with mm/submm arrays. After her PhD thesis in 1991, at the Universities of Grenoble
and Toulouse (France), she opted for a PostDoctoral position at IRAM. She was nominated Assistant Astronomer in 1994
at Observatory of Grenoble, but remained detached to IRAM until 2001, in charge of the calibration of the IRAM array.
She moved back to the Observatory of Grenoble in 2001, and then at Observatory of Bordeaux in 2003, where she became
Director of Research at CNRS in 2009. Since 2021, she acts as deputy director of Observatory of Bordeaux (OASU)
Mar. 26, 2024 ( Week 06)
Wen-Pin Hsieh
Institute of Earth Sciences, Academia Sinica
High pressure science: from atomic-scale heat transfer and superconductivity, to Earth and planetary interiors
Host: Cheng-Tien Chiang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
Recent progress in ultrafast optics and X-ray provides a unique window to track the real
time motion and dynamics of atoms and electrons as well as their complex interactions.
Extreme pressure-temperature environments can drive materials into exotic states, offering
a new platform to synthesize novel materials with potential applications. Combining
ultrafast techniques with extreme environments enables in situ probing of the dynamics of
emergent states over a wide, unexplored pressure-temperature area, which will lead to
exciting and unexpected discoveries. In this talk, I will highlight how powerful the high
pressure science and technology are, and present some examples of using ultrafast lasers
coupled with high-pressure diamond anvil cells to explore heat transfer in materials from
atomic scale to planetary interiors.
Brief Bio
Prof. Wen-Pin Hsieh received his BS (2004) and MS (2005) from NTU Physics, and PhD (2011) from UIUC
Physics. He was trained as an experimental condensed matter physicist during his undergrad, master,
doctoral, and postdoctoral training, in which he has been working on surface science, nanomaterials,
scanning probe microscopy, ultrafast optics and X-ray, nanoscale thermal transport, and high-pressure
sciences. After his two-year postdoc at Stanford, in late 2013 Prof. Hsieh joined the Institute of Earth
Sciences at Academia Sinica as an Assistant Research Fellow, and was promoted to Associate and Full
Research Fellow in 2018 and 2022, respectively. Prof. Hsieh’s major research interests are to understand
dynamic properties of materials under extremely high pressure and short time scale, with broad
applications to Geosciences, Planetary sciences, Physics, Chemistry, and Materials science. He has received
a number of awards, including Academia Sinica Presidential Scholars Program (2022-2024), Academia Sinica
Investigator Award (2022-2026), MOST Outstanding Research Award (2021), MOST Excellent Young Scholars
Research Program (2018-2021, 2021-2024), MOST Ta-You Wu Memorial Award (2019), Academia Sinica
Research Award for Junior Research Investigators (2018), Young Scholars’ Creativity Award, Foundation for
the Advancement of Outstanding Scholarship (2018), and Academia Sinica Career Development Award
(2017-2021).
Apr. 02, 2024 ( Week 07)
Chia-Ling Chien
Department of Physics and Astronomy, Johns Hopkins University
Half Quantum Flux in Spin Triplet Superconductors
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
Most superconductors (SCs) are spin singlet SCs, mainly s-wave (e.g., Nb) and some d-wave (high TC
cuprates). Spin triplet SCs are rare, essential, but difficult to identify using thermodynamic measurements and NMR Knight shift with Sr2RuO4 as a notable disappointment.
We instead use phase-sensitive method to identify triplet SCs, which have odd-parity gaps as opposed to the even-parity gaps in singlet SCs. We have observed half quantum flux (HQF) of (n + ½)Φo, where Φo = hc/2e is the flux quantum and n an integer, in sub-µm rings of spin triplet β-Bi2Pd [1], whereas integer flux nΦo has been universally observed in singlet SC rings. Noncentrosymmetric SCs with an admixture of spin triplet pairing also exhibit HQF [2]. The recent advent of kink-point upper critical field can also identify spin triplet SCs [3]. Very recently, we employ composite rings of two SCs, first proposed by by Geshkenbein, Larkin, and Barone [4], to unequivocally identity any SC, singlet or triplet [5]. Spin triplet SCs, crucial for Majorana physics and fault tolerant quantum computing, may be exploited in flux qubits.
[1] Yufan Li, Xiaoying Xu, M. H. Lee, M. W. Chu, and C. L. Chien, Science, 366, 238 (2019).
[2] Xiaoying Xu, Yufan Li, and C. L. Chien, Phys. Rev. Lett. 124, 167001 (2020).
[3] C. C. Chiang, H. C. Lee, S. C. Lin, D. Qu, M. W. Chu, C. D. Chen, C. L. Chien, and S. Y. Huang, Phys. Rev. Lett. 131, 236003 (2023).
[4] V. B. Geshkenbein, A. I. Larkin, and A. Barone, Phys. Rev. B 36, 235 (1987).
[5] Xiaoying Xu, Yufan Li, and C. L. Chien, Phys. Rev. Lett. 132, 056001 (2024).
Brief Bio
Chia-Ling Chien received his BS from Tunghai University and Ph.D. from Carnegie-Mellon University. He then went to Johns Hopkin University, where he is now the Jacob L. Hain Professor of Physics. His research interests include new materials, magnetism, spintronics, and superconductivity.
Apr. 09, 2024 ( Week 08 )
Midterm
Apr. 16, 2024 ( Week 09)
David J. Schlegel
Physics Division, Lawrence Berkeley National Laboratory
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
Apr. 23, 2024 ( Week 10)
Shi-Wei Chu
Department of Physics, National Taiwan University
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
Apr. 30, 2024 ( Week 11)
Chii-Dong Chen
Institute of Physics, Academia Sinica
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
May. 07, 2024 ( Week 12)
Vincent Tung
Department of Chemical System Engineering, School of Engineering, The University of Tokyo
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
May. 14, 2024 ( Week 13)
Yi-Chun Chen
Department of Physics, National Cheng Kung University
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
May. 21, 2024 ( Week 14)
Yen-Ting Hwang
Department of Atmospheric Sciences, National Taiwan University
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
May. 28, 2024 ( Week 15)
Boris Pioline
Laboratoire de Physique Théorique et Hautes Energies, CNRS-Sorbonne Université
TBA
Host: Ssu-Yen Huang
Time: 2:20 pm - 4:20 pm
Place: Room 104, CCMS-New Phys. building
Abstract
TBA
Brief Bio
TBA
Jun. 04, 2024 ( Week 16 )
Final