Ultracold Triatomic Molecules : Collisions & Cooling

Harvard University, Cambridge MA

Investigators

Abstract

Atoms and molecules are the basic building blocks of nature, and their behavior is governed by the microscopic theory of matter given in quantum mechanics. One of the basic aims in physics is to investigate interactions between atoms and molecules in order to more profoundly understand complex physical systems such as computers, the internet, and the human body. Another aim is to apply quantum mechanics to invent new substances that are needed for electronics and medicine. Progress towards these aims will benefit from more detailed studies of quantum physics. This project will develop new methods to cool, trap, and manipulate molecules in order to study their quantum behavior. In particular, this project will enable new explorations with triatomic molecules in a gas at very low temperature. Low temperature is important because when they are cooled, the quantum nature of atoms and molecules is greatly amplified, thus exposing quantum phenomena to more careful examination. This project will also train students in atomic and molecular physics research methods which will help prepare them to participate in the high tech work force. The technical approach is to cool atoms and molecules using lasers and then hold them in a trap to watch how they interact. The trap is not one made of hard walls, but rather relies on creating an optical or magnetic bottle. The molecules must be cold because these traps are relatively weak; molecules that are too hot will just boil out. The researchers previously invented a way of laser cooling molecules to low enough temperatures for trapping. (Cooling atoms had already been accomplished.) The cold atoms and molecules will be suspended in an otherwise nearly perfect vacuum, never touching a solid matter wall. The researchers will study in detail what happens when atoms and molecules interact, the first most basic step in the creation of more complex atomic systems. The goal of the work is to observe the exchange of energy and other phenomena in increasingly complex atom-molecule collisions, starting using triatomic molecules as a fundamental testbed. This will add to the understanding of nature and help science to design new physical systems and new quantum tools. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.