TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.4.6.036
TI  - Current-induced magnetization hysteresis defines atom trapping in a superconducting atomchip
PY  - 2018/06/22
UR  - https://scipost.org/SciPostPhys.4.6.036
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 4
IS  - 6
SP  - 036
A1  - Diorico, Fritz
AU  - Minniberger, Stefan
AU  - Weigner, Thomas
AU  - Gerstenecker, Benedikt
AU  - Shokrani, Naz
AU  - Kurpias, Zaneta
AU  - Schmiedmayer, Jörg
AB  - The physics of superconducting films, and especially the role of remnant magnetization has a defining influence on the magnetic fields used to hold and manipulate atoms on superconducting atomchips. We magnetically trap ultracold ^{87}Rb atoms on a 200{\mu}m wide and 500nm thick cryogenically cooled niobium Z wire structure. By measuring the distance of the atomcloud to the trapping wire for different transport currents and bias fields, we probe the trapping characteristics of the niobium superconducting structure. At distances closer than the trapping wire width, we observe a different behaviour than that of normal conducting wire traps. Furthermore, we measure a stable magnetic trap at zero transport current. These observations point to the presence of a remnant magnetization in our niobium film which is induced by a transport current. This current-induced magnetization defines the trap close to the chip surface. Our measurements agree very well with an analytic prediction based on the critical state model (CSM). Our results provide a new tool to control atom trapping on superconducting atomchips by designing the current distribution through its current history.
ER  -

@Article{10.21468/SciPostPhys.4.6.036,
	title={{Current-induced magnetization hysteresis defines atom trapping in a superconducting atomchip}},
	author={Fritz Diorico and Stefan Minniberger and Thomas Weigner and Benedikt Gerstenecker and Naz Shokrani and Zaneta Kurpias and Jorg Schmiedmayer},
	journal={SciPost Phys.},
	volume={4},
	pages={036},
	year={2018},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.4.6.036},
	url={https://scipost.org/10.21468/SciPostPhys.4.6.036},
}