Orateur
Dr
Christophe Vaillant
(Durham University)
Description
Dense Feshbach spectra in ultracold collisions that are chaotic cannot
be analyzed in the same way as has been done for alkali metals. In
particular, good quantum numbers cannot be assigned to individual
resonances in chaotic systems, such as ultracold Er+Er and Dy+Dy.
Instead, a statistical approach must be taken.
We have calculated and statistically analyzed the Feshbach spectrum of
ultracold collisions between Yb($^1$S$_0$) and Yb($^3$P$_2$) atoms. The
strongly anisotropic potential of this system leads to chaotic
signatures when a magnetic field is applied. We probe these chaotic
signatures by examining Feshbach resonances as functions of both
external magnetic field and an interatomic potential scaling factor
$\lambda$. We find that the statistics of the Feshbach resonances with
respect to $\lambda$ show a transition from random behaviour at zero
magnetic field to chaotic behaviour at finite field. Feshbach resonances
as a function of magnetic field also show strong signs of chaos.
The results are a step towards characterizing the conditions required
for the emergence of chaos, and demonstrate that a complicated
electronic structure is not a prerequisite for chaos.
Auteur principal
Dr
Christophe Vaillant
(Durham University)
Co-auteurs
Dr
Dermot Green
(Queen's University Belfast)
Prof.
Jeremy Hutson
(Durham University, UK)
Dr
Masato Morita
(Durham University)
M.
Matthew Frye
(Durham University)
