CHAPTER 7: Role of Resonances at Ultracold Temperatures

The revolution that has taken place in atomic, molecular, and optical (AMO) physics and physical chemistry since the early 2000s has been made possible by a variety of techniques allowing experiments to reach ultracold temperatures, and to control the interactions between particles. One of the most important tools in the modern ultracold toolkit is the ability to modify and control the behavior of ultracold samples by using resonances. Those resonances can take a variety of forms, such as shape resonances, tunable Feshbach resonances, or lasers resonant with specific states. In this chapter, we review some of the concepts relevant to the study of resonances in ultracold chemical systems, and give a few examples of their applications.