April 25, 2016 – April 28, 2016

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Location

Institute of Advanced Studies, Hong Kong University of Science and Technology, Hong Kong, China

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Organizers

Deigo Dalvit, Los Alamos National Laboratory
Ho Bun Chan, Hong Kong University of Science and Technology
Daniel Lopez, Argonne National Laboratory
Stefan Buhmann, University of Freiburg
George Palasantzas, University of Groeningen

Overview

http://iasprogram.ust.hk/201604casimir/index.html

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This workshop will focus on recent developments in the fields of Casimir and van der Waals (vdW) interactions and the prospects on novel applications of these forces. Casimir forces between macroscopic surfaces have the same physical origin as atom-surface interactions and those between two atoms or molecules (van de Waals forces), as they all arise from quantum fluctuations. Casimir forces between macroscopic surfaces involve separations typically larger than 100 nm where retardation plays an important role, while van der Waals forces often refer to separations smaller than a few nm where retardation is negligible. Traditionally, these closely related phenomena have been studied in two very active but separate communities, and despite the close scientific connections, researchers in these two areas rarely have opportunities to gather together to exchange ideas. The proposed workshop is unique because it will be the first to bring together the Casimir and van der Waals communities and inspire cross-fertilization. It will provide an opportunity for theorists and experimentalists in these two fields to get together, fostering interdisciplinary discussion and collaborations for further advances. 

Van der Waals/Casimir interactions are of fundamental interest as they arise from fluctuations. For example, quantum and/or thermal fluctuations of the electromagnetic field give rise to the Casimir force between two conductors, and charge fluctuations mediated by electromagnetic fields result in London dispersion forces in molecular systems. Research in these fields is highly interdisciplinary, involving knowledge in diverse topics in nanomechanics and high sensitivity force detection, surface science, solid state physics, classical electrodynamics, quantum physics, quantum chemistry, computational physics, and biology. Apart from fundamental interests, van der Waals/Casimir interactions are also of technological importance because of their relevance in chemical and biological processes, and micro- and nano-machinery. In the last two decades, advances in theoretical studies and experimental techniques have enabled investigation of the Casimir force beyond the original configuration of two parallel perfect metal plates. Novel materials and shapes of the interacting bodies enable new opportunities for applications and, at the same time, pose new open questions. One topic of current interests involves the finite temperature corrections to the Casimir force and non-equilibrium Casimir forces where the interacting objects are at different temperatures. Another area under active discussion is the possibility of generating non-monotonic or repulsive Casimir forces between objects made of materials with novel optical properties or of unconventional shapes. Topics of active research in van der Waals physics include vdW interactions for electronically excited systems, the impact of surface absorbants and solvents, non-local and non-additivity effects, and precision measurements of forces at short separations with high quality (geometry and chemistry) surfaces. 

Traditionally, most of the Casimir force measurements are performed with a vacuum gap separating the interacting bodies. Studies of vdW forces, on the other hand, may involve a much wider range of materials, from liquids to biological systems. Recently, experimentalists in the Casimir community started to venture into systems involving liquids. Such efforts proved to be highly worthwhile, evident from the successful demonstration of the repulsive Casimir force for the first time. It is likely that discussions with colleagues in the vdW community will further expand the systems of interests to the researchers in Casimir effect. Secondly, atomic force microscopes are indispensable tools for experimental investigations of both Casimir and vdW forces. Apart from atomic force microscopes, the Casimir community uses a number of other micromechanical devices for force measurement, such as torsional oscillators and nanomechanical beams. The proposed workshop provides an opportunity for researchers in these two fields to share their toolkits in high sensitivity force measurements, planting the seed for a new generation of experiments. Similarly, on the theory side, the two communities can share modeling and simulation techniques in order to bridge time and length scales inherent to vdW and Casimir phenomena. For example, the ab initio methods recently developed to compute many-body correlation vdW energies can be extremely useful to predict the optical response of materials in the meso- and macro-scales, which are the input to all calculations in Casimir physics based on macroscopic fluctuational electrodynamics, e.g. Lifshitz theory. 

List of invited speakers and topics (tentative)
1. Mauro Antezza, University Montpellier (France): Non-equilibrium Casimir forces
2. Ludmila Boinovich*, Russian Academy of Sciences (Russia): Surface forces
3. Federico Capasso, Harvard University (USA): Applications of Casimir forces
4. Ricardo Decca**, Indiana University-Purdue University Indianapolis (USA): Casimir force measurements with torsional balance
5. John Dobson, Griffith University (Australia): van der Waals forces in nano-material
6. Thorsten Emig, MIT (USA): Critical Casimir forces in binary liquids
7. Karin Jacobs*, University of Saarland (Germany): Soft condensed matter and vdW interactions
8. Galina Klimchitskaya*, North-West Technical University (Russia): Casimir interaction with graphene
9. Astrid Lambrecht*, CNRS (France): Geometry effects in Casimir interactions
10. Steve Lamoreaux, Yale University (USA): Casimir force experiments
11. Carsten Henkel, Postdam (Germany): Casimir-Polder physics in atom chips
12. Kimball Milton, University of Oklahoma (USA): Field theory in Casimir physics
13. Umar Mohideen, UC Riverside (USA): Casimir force measurements with atomic force microscopes
14. Jeremy Munday, University of Maryland (USA): Casimir torque measurements with liquid crystals
15. Paulo Maia Neto**, Physics Institute, Federal University Rio de Janeiro (Brazil): Casimir force measurements with optical traps
16. Sir John Pendry, Imperial College (UK): Quantum friction
17. Rudolf Podgornik, University of Ljubljana (Slovenia): van der Waals forces in biological systems
18. Alejandro Rodriguez**, Princeton University (USA): Numerical methods for Casimir interactions
20. Alexander Tkatchenko, Fritz Haber Institute (Germany): First principles calculations of van der Waals forces
21. Lilia Woods*, University of South Florida (USA): Casimir interactions in 2D Dirac systems
22.Roya Zandi*, University of California at Riverside (USA): Statistical mechanics of fluctuation-induced interactions.