Department of Physics and Astronomy and The Institute of Optics, University of Rochester
Talk Title:
History and solution of the phase problem in the theory of structure determination of crystals from X-ray diffraction experiments
Tea Time:
3:30 pm
Tea Location:
Bausch & Lomb Lobby
Description:
Since the pioneering work of Max von Laue on interference and diffraction of X-rays carried out almost a hundred years ago, numerous attempts have been made to determine structures of crystalline media from X-ray diffraction experiments. Usefulness of all of them has been limited by the inability of measuring phases of the diffracted beams.
In this talk the most important researches carried out in this field will be reviewed and a recently obtained solution of the phase problem will be presented.
School of Engineering and Applied Sciences, Harvard University
Talk Title:
Sub-wavelength Photonics: from light manipulation to quantum levitation at the nanoscale
Tea Time:
3:30 pm
Tea Location:
Bausch & Lomb Lobby
Description:
Surface Plasmon Polaritons (SSPs) allow one to achieve concentration of light into sub-wavelength regions thus opening up rich new directions in physical optics and photonics. A wide range of phenomena and applications across a spectral range from the visible to the mid-infrared, made possible by SPPs and by advanced fabrication techniques (from Focused ion Beam to new soft lithography techniques that enable patterning of large area substrates of nearly arbitrary shape and composition) will be presented in this talk. They include: (a) plasmonic collimators that have allowed to dramatically reduce the divergence of semiconductor lasers, creatingexciting opportunities in beamengineering; (b) plasmonic polarizers for arbitrary control of laser polarization; (c) new light sources such as plasmonic laser antennas, capable of creating intense nanospots for spatially resolved chemical imaging and ultra high density optical storage (d)antenna arrays for surface enhanced Raman scattering; (e) frequency selective surfaces enabled by a new soft lithography technique; (f) attractive and repulsiveoptomechanical forces between dielectric and plasmonic waveguides at sub-wavelength distances. Finally at nanoscale distances forces arising from quantum fluctuations of the electromagnetic field cannot be neglected give rising to both attractive and repulsive Casimir forces. The latter, recently measured by us for the first time, could lead to ultralow friction mechanical devices based on quantum electrodynamical levitation.
Event Date:
Wednesday, February 17, 2010 - 3:45pm
Event Location:
Bausch & Lomb 106
Speaker:
Dr. Sidney R. Nagel
Affiliation:
University of Chicago
Talk Title:
TBA
Tea Time:
3:30 pm
Tea Location:
Bausch & Lomb Lobby
Description:
Event Date:
Wednesday, February 3, 2010 - 3:45pm
Event Location:
Bausch & Lomb 106
Speaker:
Prof. Amitava Bhattacharjee
Affiliation:
University of New Hampshire
Talk Title:
TBA
Tea Time:
3:30 pm
Tea Location:
3:30 pm
Description:
Event Date:
Wednesday, November 4, 2009 - 3:45pm
Event Location:
Bausch & Lomb 106
Speaker:
Prof. Joseph Polchinski
Affiliation:
Dept. of Physics, Kavli Institute for Theoretical Physics University of California at Santa Barbara
Talk Title:
Gauge/Gravity Duality
Tea Time:
3:30 pm
Tea Location:
Bausch & Lomb Lobby
Description:
Gauge theories, which describe the particle interactions, are well understood, while quantum gravity has many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand this provides our most precise description of quantum gravity, and resolves some long-standing paradoxes. On the other, it gives a new perspective on the strong interaction; for example, some properties of heavy ion collisions are best modeled by black holes. I describe these ideas, and discuss current and future directions.
