- Experiments with an ultracold Fermi gas -new prospective of tackling old condensed matter problems
Experiments with an ultracold Fermi gas -new prospective of tackling old condensed matter problems
The collective behavior of an ensemble of strongly interacting fermions is central to many physical systems, including high-Tc superconductors, heavy fermion materials, liquid 3He, quark-gluon plasma, neutron stars, and ultracold Fermi gases. Theoretical understanding of these systems is challenging due to the many-body nature of the problem and the lack of an obvious small parameter for a perturbative analysis. In this lecture I will introduce you to our experimental system, in which we use lasers to trap fermionic atoms (40K) in two internal spin states, and cool them down to ultralow temperatures while still maintaining their gaseous state. Similar to electrons in a metal, at low enough temperatures the spins pair and condense while creating a fermionic superfluid. This is an ideal model system to shed light on long-standing many-body problems, as it provides excellent controllability, reproducibility, and unique detection methods. I will describe several of these detection methods developed at JILA, which provide invaluable insight into the many-body state of the system. The talk will conclude with an overview of the open questions and future challenges we and others are facing.
Dr. Yoav Sagi received his B.Sc. in physics and mathematics from the Hebrew University in Jerusalem in 1999, as part of the prestigious Talpiot excellence program. He received the Physics M.Sc. from the Technion, Israel Institute of Technology, in the field of quantum optics and quantum information. For his PhD, he moved into the field of ultracold atoms, joining Prof. Nir Davidson at the Weizmann Institute of Science. At 2010, Dr. Sagi joined Prof. Deborah Jin from JILA (Boulder, CO). His postdoctoral research is focused on extracting quantities of a homogeneous Fermi gas, in a system which is intrinsically inhomogeneous because of the confining potential. Dr. Yoav Sagi won several prizes and fellowships, including the John F. Kennedy Award (highest prize conferred by the Feinberg Graduate School at the Weizmann Institute of Science), the Rothschild postdoctoral fellowship, and the Fulbright fellowship (which I declined). His PhD work was published as a book in the Springer Theses series (“recognizing outstanding Ph.D. research“). Dr. Yoav Sagi will start a new experimental group this summer in the Physics department in the Technion, Israel.