Dvořákovy přednášky


Vladimír Dvořák (1934–2007)

Významný český vědec, který pracoval ve fyzice pevných látek. Zabýval se teorií feroelektrických látek a strukturálních fázových přechodů. Celý svůj produktivní život spojil s Fyzikálním ústavem. Byl jeho ředitelem v letech 1993-2001. Členem Učené společnosti byl od r. 1995. Byl protagonistou revolučních reforem ve Fyzikálním ústavu po roce 1989. K uctění této osobnosti a jeho práce organizuje Fyzikální ústav každoročně slavnostní Dvořákovu přednášku, přednesenou mezinárodně uznávanou autoritou v některém z oborů výzkumu Fyzikálního ústavu.


Electric Field Control of Magnetism: From Global Markets to Spin Orbit Coupling

The 11th Dvořák Lecture
prof. Ramamoorthy Ramesh
Department of Physics and Department of Materials Science and Engineering, University of California, Berkeley, USA

The emergence of the “Internet of Things” and the explosion of Artificial Intelligence/Machine Learning applications are likely to push up significantly the market for microelectronics. The related energy consumption could increase by 20–25%. Thus, looking for a new generation of ultralow-power memories and switches is an area of significant current research. Perovskite oxides exhibit a rich spectrum of functional responses, including magnetism, ferroelectricity,...

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Molecular Understanding, Design and Development of Ultra-Low Fouling Zwitterionic Materials

The 10th Dvořák Lecture
prof. Shaoyi Jiang
Department of Chemical Engineering, University of Washington, Seattle, USA

An important challenge in many applications, ranging from biosensors to drug delivery, is the prevention of nonspecific protein adsorption on surfaces. To address this challenge, our goals are twofold. First, we strive to provide a fundamental understanding of nonfouling mechanisms at the molecular level using an integrated experimental and simulation approach.

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Advanced scintillators for fast timing applications

The 9th Dvořák lecture
Prof. Paul Lecoq
CERN, Geneva, Switzerland

The future generation of radiation detectors is more and more demanding on timing performance for a wide range of applications, such as time of flight (TOF) techniques for PET cameras in medical imaging and particle identification in nuclear physics and high energy physics detectors, precise event time tagging in high luminosity accelerators and a number of photonic applications based on single photon detection.

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Gravitational-wave astrophysics

The 8th Dvořák Lecture
Prof. Marco Cavaglià
Department of Physics and Astronomy, University of Mississippi, USA

In 1916 Albert Einstein demonstrated that the theory of General Relativity allows for wave-like, space time perturbations propagating with the speed of light. Two years later, he calculated his famous quadrupole formula, describing how these “gravitational” waves can be generated. However, due to the extreme weakness of gravity, detecting gravitational waves seemed an impossible task. They even became a matter of controversy with Einstein himself becoming convinced they did not exist. It took several decades before the first attempts to detect gravitational waves started in the sixties with the pioneering work of Joseph Weber. Although the orbital decay of the PSR B1913+16 binary pulsar provided an indirect proof of the existence of gravitational waves, their direct detection remained nevertheless elusive. The long quest to detect gravitational waves finally ended on February 11, 2016, when scientists from the Laser Interferometer Gravitational-wave Observatory (LIGO) Scientific Collaboration and the Virgo Collaboration announced the first detection of a gravitational-wave signal from a merger of two stellar mass black holes.

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X-ray lasers and the challenges facing structural sciences

The 7th Dvořák Lecture
Prof. Janos Hajdu
Laboratory of Molecular Biophysics, Uppsala University, Sweden & the European XFEL GmbH, Hamburg, Germany

Theory predicts that with an ultra-short and extremely bright coherent X-ray pulse, a single diffraction pattern may be recorded from a large macromolecule, a virus, or a cell before the sample explodes and turns into a plasma. The over-sampled diffraction pattern permits phase retrieval and hence structure determination. X-ray lasers capable to deliver ultra bright and very short X-ray pulses for such experiments have recently started operations. Free-electron lasers are the most brilliant sources of X-rays to date, exceeding the peak brilliance of conventional synchrotrons by a factor of 10 billion, and improving. In the duration of a single flash, the beam focused to a micron-sized spot has the same power density as all the sunlight hitting the Earth, focused to a millimetre square. The interaction of an intense X-ray pulse with matter is profoundly different from that of an optical pulse. Our aim in biology is to step beyond conventional damage limits and develop the science and technology required to enable high-resolution imaging of biological objects. The talk will summarise imaging results from the Linac Coherent Light Source, including studies on live cyanobacteria.

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The LASER: a Historical Perspective

The 6th Dvořák Lecture
Orazio Svelto
Politecnico di Milano, Italy

From the race to make the first laser to early developments in laser science, a description will be made of the most important achievements. Likewise, the birth of nonlinear optics and the ad- vent of ultrafast laser science will also be considered. In any case, a very coarse review of some of the most important achievements will be presented, with the addition of a few anecdotes and curiosities as derived by the personal reminiscence of the author. So far, 21 scientists have been awarded the Nobel Prize for research- es on lasers or with lasers. A coarse review and some critical historical connection between these awards will also be considered.

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The long journey to the Higgs boson and beyond at the LHC

The 5th Dvořák Lecture
Peter Jenni
University of Freiburg, Germany and CERN, Geneva, Switzerland

Since three years the experiments at the Large Hadron Collider (LHC), in particular ATLAS, investigate particle physics at the highest collision energies ever achieved in a laboratory. Following a rich harvest of results for Standard Model (SM) Physics came in 2012 the first spectacular discovery of a new, heavy particle, most likely the long-awaited Higgs boson. The latest results with the full data set accumulated over the first three-years running period of the LHC will be presented. Other, far-reaching results can already be reported for exploratory new physics searches like Supersymmetry (SUSY) and its implication for Dark Matter in the Universe, Extra Dimensions, and the production of new heavy particles.

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Graphene Ten Years Later

The 4th Dvořák Lecture
Prof. Allan H. MacDonald
The University of Texas at Austin, USA

Graphene is an atomically two-dimensional material which was first isolated for electronic property studies by Novoselov, Geim and collaborators from the University of Manchester about ten years ago. It is a gapless semiconductor formed entirely from carbon atoms and can be viewed as a giant aromatic molecule. Graphene’s honeycomb lattice structure is bipartite; atoms on one sublattice have three nearest neighbours all on the other sublattice. Its conduction and valence band states are both formed from graphene π-bands and differ only in the phase difference between their sublattice projections. Because it is two-dimensional, its carrier density can be tuned over a broad range without introducing dopants.

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Superfluid Helium-3: From very low Temperatures to the Big Bang

The 3rd Dvořák Lecture
Prof. Dieter Vollhardt
University of Augsburg, Germany

Since their discovery in 1971 the superfluid phases of Helium-3 have proved to be the ideal testing ground for many fundamental concepts of modern physics. Phenomena such as Cooper pairing, macroscopic quantum coherence, spontaneous breaking of high symmetries, and the formation of exotic topological defects are not only an important enrichment of the physics of condensed matter, but also provide important links to particle physics, the structure of the early universe and, most recently, quantum turbulence. In my lecture I will present a simple introduction into the physics of superfluid Helium-3, and describe the progress made in this fascinating field of basic research.

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Quantum Information and the Foundations of Quantum Mechanics

The 2nd Dvořák Lecture
Prof. Anton Zeilinger
University of Vienna, Austria

Research on the foundations of quantum mechanics has given rise to the field of quantum information science. It should be stressed that this research beginning around the 1970s was not motivated by search for applications but rather by pure fundamental curiosity. Today, quantum computation, quantum teleportation, quantum communication, or quantum cryptography are novel concepts in information technology with no classical parallel. The resulting experimental development in quantum information science has renewed the debate about the foundations of quantum mechanics and it has led to unprecedented control of quantum systems. All this again opens up the door for novel fundamental experimental research directions. For example, the high-precision control of entangled photon states even over distances as large as those between the two Canary Islands of Tenerife and La Palma allows novel tests of the concepts of nonlocality and realism. Or, to mention another example, the development of quantum microoptics opens up new experiments in higher-dimensional Hilbert spaces. Such experiments in turn will again give rise to novel possibilities in quantum information science.

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Thermodynamic Approach to Nano-Inhomogeneous Ferroelectrics

The 1st Dvořák Lecture
Prof. Yoshihiro Ishibashi
Nagoya University, Japan

Collaboration with Vladimir Dvorak started when he stayed in Nagoya for three months in 1975, and lasted until his final days. His visit to Nagoya gave me big stimuli and benefits. I could learn how to apply the group theory to phase transitions directly from him, and since then we could jointly make a certain contribution to the progress of the theory of ferroelectric phase transitions. Among our joint works, the most memorable one is the development of the theory of the incommensurate phase transitions, of which much was not known at that time. This subject had been already discussed among us during his stay, but the first joint paper reporting results of research appeared in J. Phys. Soc. Japan in January 1978, more than two years after his return to Prague. I am now reminded fondly of great patience required in Prague and Nagoya in the days of air-mail communication at the best.

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