Friday, November 18, 2011, 3pm
Innovation Hall room 136
Ian B. Spielman
Fellow, Joint Quantum Institute
National Institute of Standards and Technology
and the University of Maryland
Atoms: Understanding Complex Systems Through Simplicity
What is the origin of complexity? This simple question
underlies some of the must fundamental problems in science: how can
simple chemical components organize themselves into living cells and
organisms? What governs order on the astronomical scale?
While these examples involve numerous distinct interacting
components, similar order appears in systems of identical particles all
with the same interactions. Complexity from simplicity: this
is fundamental physics.
Nowhere is such complexity more common than in solids where innumerable
electrons interact with the familiar Coulomb law, yet scaling up we can
get different materials such as semiconductors, metals,
superconductors, magnets, and so forth. How do these work?
Some we understand, and some like high-temperature
superconductors, we do not.
Seemingly simple, electrons moving in a crystal are still moving in a
complicated environment; an intricate crystal structure, random
imperfections, and a myriad of other details make it difficult to
formulate simple laws that predict behavior.
In contrast, systems of ultra-cold atoms -- tenuous vapors of atoms
cooled to just a billionth of a degree above absolute zero -- truly
allow us to ask and answer the question "how does order appear from
simplicity?" In a realm where quantum mechanics rules, we
create atomic systems that are analogous to more complex material
systems, allowing us to better understand the fundamental reason for
physical effects. In my talk I will answer such common party
questions as: How neutral atoms can experience the Lorentz force?
And, what can cold atoms tell us about spintronics?