# Steck Group Research

Daniel Steck’s research interests are rooted in the physics of ultracold atoms. In particular, he is interested in problems that cross over into the subject of nonlinear dynamical systems, a fascinating, interdisciplinary area. The intersection of these two areas addresses a range of problems from nonlinear behavior, such as pattern formation and solitonic propagation, to controlling quantum systems and quantum chaos. The arena for these experiments in quantum nonlinear dynamical systems is atom optics, where ultracold atoms can be subjected to essentially arbitrary potentials made from laser light.

One particularly intriguing question arises in the area of quantum chaos—the study of quantum systems that are chaotic in the classical limit. It is now well known that quantum effects suppress classical chaos. This statement appears to pose problems for the correspondence principle, however, since classical systems are composed of atoms, which are fundamentally quantum mechanical. Somehow, classical chaos must emerge from quantum systems even though chaos does not seem to be compatible with quantum mechanics. Decoherence, arising from coupling of a quantum system to its external environment, provides one resolution. A modern twist on this focuses on a continuous measurement process—a process implicit in the concept of a classical trajectory.