Fig. 2: Creation of a superconducting vortex‒antivortex pair via MFM.
From: Vortex confinement through an unquantized magnetic flux
a Schematics illustrating the creation of superconducting vortex‒antivortex pairs (SVAPs) via an in-plane magnetized MFM tip. SVAPs (red dots) and trapped interstitial vortices (TIVs, green dots) are generated by the tip, whereas regular vortices (blue dots) are formed by the stray field of the system. b Illustration of the SVAP configuration created by the MFM tip. Antivortices (white dots) are induced by both the external stray field and the tip field, whereas SVAPs (red dots) and TIVs (dark green dots) represent confined vortices. The yellow arrow indicates the position of the MFM tip during the SVAP creation process. c, d MFM images obtained from two separate experiments with the same conditions and a shifted scan frame. The yellow arrow indicates the position of the MFM tip, which remains at a fixed tip‒sample distance of 600 nm during SVAP formation. The bright dots in the MFM image correspond to antivortices, whereas the dark dots represent vortices.
