Demonstration of fold and cusp catastrophes in an atomic cloud reflected from an optical barrier in the presence of gravity.
We experimentally demonstrate first-order (fold) and second-order (cusp) catastrophes in the density of an atomic cloud reflected from an optical barrier in the presence of gravity and show their corresponding universal asymptotic behavior. These catastrophes, arising from classical dynamics, enable robust, field-free refocusing of an expanding atomic cloud with a wide velocity distribution. Specifically, the density attained at the cusp point in our experiment reached 65% of the peak density of the atoms in the trap prior to their release. We thereby add caustics to the various phenomena with parallels in optics that can be harnessed for manipulation of cold atoms. The structural stability of catastrophes provides inherent robustness against variations in the system's dynamics and initial conditions, making them suitable for manipulation of atoms under imperfect conditions and limited controllability.
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Serge
S
Rosenblum
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Orel
O
Bechler
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Itay
I
Shomroni
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Roy
R
Kaner
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Talya
T
Arusi-Parpar
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Oren
O
Raz
Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Barak
B
Dayan