Loading a quantum gas from a hybrid dimple trap to a shell trap

TL;DR

This paper demonstrates an efficient method to transfer a degenerate Bose gas from a hybrid trap to a shell-shaped magnetic trap using adiabatic potentials and rf evaporation, achieving minimal excitation.

Contribution

It introduces a novel loading technique for quantum gases into shell traps via adiabatic transfer from hybrid traps, enhancing control and efficiency.

Findings

Successful loading of Bose gas into shell trap

Adiabatic transfer limits center-of-mass excitation

Efficient rf evaporation in hybrid trap

Abstract

Starting from a degenerate Bose gas in a hybrid trap combining a magnetic quadrupole trap and an attractive optical trap resulting from a focused laser beam, we demonstrate the efficient loading of this quantum gas into a shell-shaped trap. The shell trap is purely magnetic and relies on adiabatic potentials for atoms in an inhomogeneous magnetic field dressed by a radiofrequency (rf) field. We show that direct rf evaporation in the hybrid trap enables an efficient and simple preparation of the cold sample, well adapted to the subsequent loading procedure. The transfer into the shell trap is adiabatic and limits the final excitation of the center-of-mass motion to below 2 micrometres.