Spinor Bose-Einstein Condensates and Quantum Antiferromagnetism

Abstract

Bose-Einstein condensates (BECs) have revolutionized atomic physics, a revolution which, sixteen years after their discovery, shows little sign of stopping. The attention of the quantum gases community has increasingly shifted from studies of broad features of the many-body condensed state to more specific realizations based upon control of spin state, trapping geometry, dimensionality and temporal behavior. In many regards quantum gases have no direct counterpart in condensed matter, although many parallels do exist, and these serve to guide efforts at the interface between disciplines. Experiments in our laboratory investigate the spinor nature of a sodium BEC, an example of a quantum antiferromagnet. The interplay between the quadratic Zeeman effect and spin-spin interactions gives rise to a rich phase diagram of possibilities. In this talk I will describe experiments that explore the dynamical behavior of such a BEC in the vicinity of a quantum phase transition. Our work highlights the experimental knobs and probes that are available to explore these fascinating quantum systems.