Direct loading of atoms from a macroscopic quadrupole magnetic trap into a microchip trap

Direct loading of atoms from a macroscopic quadrupole magnetic trap into a microchip trap

Jun Cheng;Jing-fang Zhang;Xin-ping Xu;Hai-chao Zhang;Yu-zhu Wang

【期刊名称】《中国物理：英文版》 【年(卷),期】2017(026)003

【摘要】We demonstrate the direct loading of cold atoms into a microchip 2-mm Z-trap,where the evaporative cooling can be performed efficiently,from a macroscopic quadrupole magnetic trap with a high loading efficiency.The macroscopic quadrupole magnetic trap potential is designed to be moveable by controlling the currents of the two pairs of anti-Helmholtz coils.The cold atoms are initially prepared in a standard six-beam magneto-optical trap and loaded into the macroscopic quadrupole magnetic trap,and then transported to the atom chip surface by moving the macroscopic trap potential.By means of a three-dimensional absorption imaging system,we are able to optimize the position alignment of the atom cloud in the macroscopic trap and the microchip Z-shaped wire.Consequently,with a proper magnetic transfer scheme,we load the cold atoms into the microchip Z-trap directly and efficiently.The loading efficiency is measured to be about 50％.This approach can be used to generate appropriate ultracold atoms

sources,for

example,for

a

magnetically

guided

atom

interferometer based on atom chip.