Events at Physics |
Events on Friday, February 22nd, 2008
- Special Atomic Physics Seminar
- Engineering a Quantum Information Processor
- Time: 10:00 am
- Place: 5280 Chamberlin Hall
- Speaker: Professor Jungsang Kim, Duke University
- Abstract: Fundamental advantage of utilizing quantum resources for computation and communication has been discovered in the last two decades. Experimental demonstration of representing and manipulating quantum bits in physical systems and simple quantum algorithms followed. While the experimental research in this field has progressed at a rapid pace, the notion of a practical information processor based on quantum physics still faces tremendous amount of challenges. Construction of a scalable quantum information processor is a system design challenge that requires cutting-edge technology guided by engineering principles. The task requires expertise in quantum physics, computer architectures and integrated microsystems technology, and lots of exciting research is still to be done. In this talk, I will discuss the multidisciplinary challenge of designing a quantum information processor, and some of the technology progress made to date. I will present micro electromechanical systems (MEMS) technology applied to creating a beam control system that can address quantum bits represented by atoms trapped in a ultra-high vacuum chamber.
- Phenomenology Seminar
- Matching NLO Calculations with Parton Shower: the POsitive-Weight Hardest Emission Generator
- Time: 2:30 pm
- Place: 5280 Chamberlin Hall
- Speaker: Carlo Oleari, Univ. di Milano-Bicocca
- Physics Department Colloquium
- Visualizing Pair Formation and the Riddle of High-Temperature Superconductivity
- Time: 4:00 pm
- Place: 2241 Chamberlin Hall (coffee at 3:30 pm)
- Speaker: Ali Yazdani, Princeton University
- Abstract: The pairing of electrons underlies the formation of a superconducting state with zero electrical resistance. After twenty years of work, the mechanism of pairing and the temperature at which pairs first form in high-temperature copper-oxide superconductors are still hotly debated. Do pairs form at the critical temperature like conventional superconductors? Is pairing mediated by a bosonic excitation, as in conventional BCS superconductors, or is pairing with d-wave symmetry an unavoidable consequence of strong Coulomb repulsion in these compounds? In search of experimental answers to these important questions, we have develop several new techniques, based on the scanning tunneling microscope (STM), to visualize the process of pair formation on the atomic scale and to probe what controls the strength of pairing in these compounds with high precision. We show that pairing in the cuprates is strongly local, with pairs forming in nanoscale regions of samples over a range of temperatures above the critical temperature. I will discuss these experiments and other high resolution studies of electronic states in search of clues as to what controls the strength of the pairing interaction in the cuprates.
- Host: Chubukov