Plenary
"Quantum Black Holes and the Structure of Space and Time"
Gerard 't Hooft
Utrecht University
Time: 1 pm, Oct 25 (Wed)
Location: Room 300C
Abstract
Theories of strings and D-branes can be used to describe objects that may be regarded as black holes or candidates thereof, but leave some properties of horizons and space-time structure underdeveloped. Yet one can also start off with black hole models using not much more than standard quantum field theory in combination with perturbative gravity. Then also, one can take gravitational back reaction into account, and find out where information is stored and how out-going particles are entangled. This yields a remarkably clear picture of the non-trivial space-time structure of black holes.
2017 가을 물리학회에는 1999년 노벨상 수상자이자 양자 게이지이론, 양자 중력, 자기 단극 이론의 세계적 권위자이신 Gerard 't Hooft 교수님 (Utrecht University, 네덜란드)을 기조강연자로 모시게 되었습니다. [Prof. Gerad ‘t Hooft (Utrecht University), the 1999 Nobel Prize laureate, will present a plenary talk. He is known for his works on gauge theory, quantum gravity, and magnetic monopole.]
Education
Gymnasium-Beta, Dalton Lyceum, The Hague, 1964
Physics and Mathematics, University of Utrecht
Promotie (PhD thesis) on the subject ``Renormalization Procedure for Yang-Mills fields'', 1 March 1972
Professions
Full Professor, Utrecht University, from 2 February 1977
Ambassador for Mars One, the organization whose aim it is to establish a permanent human settlement on the Planet Mars
Honours and awards:
Dannie Heineman Prize, New York, 30 January 1979
Wolf Prize of the State of Israel, 21 March 1982
Pius XI Medal, Vatican, 12 November 1983
Lorentz Medal, KNAW, Amsterdam, 24 November 1986
Spinoza Premium, Netherlands Organization for Scientific Research NWO, June 1995
The 1999 Nobel Prize in Physics, with M. Veltman, awarded by The Royal Swedish Academy of Sciences, Stockholm, Citation: "For elucidating the quantum structure of electroweak interactions in physics", 10 December 1999
Commandeur in de Orde van de Nederlandse Leeuw, 14 October 1999
Officier de la Légion d'Honneur, awarded by the Ambassador of France at the Hague, 9 February 2001
Honorary Doctor of Science, University of Chicago, Illinois, USA, 15 December 1981
Honorary Doctor of Science, University of Leuven, Belgium, 2 February 1996
Honorary Doctorate, University of Bologna, Italy, 10 October 1998
FIAS (Frankfurt Institute for Advanced Studies) Senior Fellow Laureatus, realized by Carlo and Karin Giersch, through the Stiftung Giersch, 28 September 2016.
The Niels Bohr Institute Medal of Honour, Copenhagen, 30 November 2016.
After 1999: 9 more Honorary Doctorates.
"The Quantum Properties of Magnetic Atoms on Surfaces"
Andreas J. Heinrich
Center for Quantum Nanoscience, Institute for Basic Science, Seoul, Korea
Physics Department, Ewha Womans University, Seoul, Korea
Time: 1 pm, Oct 26 (Thu)
Location: Room 300C
Abstract
The scanning tunneling microscope is an amazing tool because of its atomic-scale spatial resolution. This can be combined with the use of low temperatures, culminating in precise atom manipulation and spectroscopy with microvolt energy resolution. In this talk we will apply these techniques to the investigation of the quantum spin properties of magnetic atoms sitting on a thin film of magnesium oxide (MgO). In such a situation, the thin insulating film serves two important purposes: first, it provides a strong ligand field which is crucial to understanding the low-energy (magnetic) states of the metal atoms (adsorbate). Second, the insulating film electronically decouples the atom from the underlying conduction electrons, which in turn preserve the quantumness of the adsorbate.
In a first set of experiments, we will investigate the tunneling spectroscopy of 3d transition metal atoms at low temperature and in high magnetic fields. We find that the tunneling electrons can interact with the magnetic states of the adsorbate by exchanging energy and quanta of angular momentum. This leads to clear selection rules in this inelastic tunneling spectroscopy, which we coined ‘spin excitation spectroscopy’ (Science 2004). Due to the strong ligand field of the polar MgO surface, we find that adsorbates with spin larger than ½ show strong magnetic anisotropy, giving rise to non-trivial magnetic states (Science 2014, PRL 2015).
On our quest towards more quantumness we will then investigate the lifetimes of excited states. After a tunneling electron excites the adsorbate, it can be left behind in an excited state. Often this lifetime is far shorter than the time resolution of traditional STM, which is in the range of millisecond. We therefore developed an all-electrical pump and probe measurement technique that allows lifetime measurements down to nanoseconds (Science 2010). Surprisingly, we find lifetimes that vary from nanoseconds to hours, a truly amazing consequence of the quantum states of the different adsorbates.
Finally, we will explore the superposition of quantum states which is inherent to spin resonance techniques. We recently demonstrated the use of electron spin resonance on single Fe atoms on MgO (Science 2015). This technique combines the power of STM of atomic-scale spectroscopy with the unprecedented energy resolution of spin resonance techniques, which is about 10,000 times better than normal spectroscopy.
하인리히 박사는 고체 내 원자 스케일에서 벌어지는 물리 현상에 관한 연구 분야를 이끌어 가는 세계적으로 가장 영향력 있는 과학자 중의 한 사람이다. 특히, 하인리히 박사는 주사터널링현미경(scanning tunneling microscope)을 이용한 스핀 여기 분광학(spin excitation spectroscopy) 분야를 개척하였는데, 이 방법을 통해서 고체 표면에 존재하는 나노 구조체와 원자들의 양자 상태를 높은 해상도로 분석할 수 있게 되었다. [Professor Heinrich is a world-leading research in the field of atomic-scale science in solids. He pioneered spin excitation spectroscopy with scanning tunneling microscopes- a method that has provided high-resolution access to the quantum states of atoms and nanostructures on surfaces.]
Education
Masters (Diplom): University of Göttingen, Germany (1994)
Ph. D. (Physics): University of Göttingen, Germany (1998)
Appointments
1998-2001 Postdoc at IBM Almaden with Dr. Donald M. Eigler
2001-2004 Researcher/Engineer at IBM Almaden
2005-2016 Research Staff Member at IBM Almaden
(Group leader on scanning probe microscopy and magnetic nanostructures on surfaces)
2016-present Distinguished Professor at Ewha Womans University
2017-present Director of Center for Quantum Nanoscience (QNS) of Institute of Basic Science (IBS)
Professional Service Activities and Recognition
2011 Best of IBM Award
2012-present Scientific Advisory Board of Max Planck Institute of Solid State Research, Stuttgart, Germany
2012 Fellow of the American Physical Society
2015 Fellow of the American Association for the Advancement of Science