Hovhannisyan Razmik A, Grebenchuk Sergey Yu, Baranov Denis S, Roditchev Dimitri, Stolyarov Vasily S
Advanced mesoscience and nanotechnology centre, Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia.
Department of Physics, Stockholm University, AlbaNova University Center, SE-10691 Stockholm, Sweden.
J Phys Chem Lett. 2021 Dec 30;12(51):12196-12201. doi: 10.1021/acs.jpclett.1c03556. Epub 2021 Dec 17.
Lateral Josephson junctions (LJJ) made of two superconducting Nb electrodes coupled by Cu-film are applied to quantify the stray magnetic field of Co-coated cantilevers used in magnetic force microscopy (MFM). The interaction of the magnetic cantilever with LJJ is reflected in the electronic response of LJJ as well as in the phase shift of cantilever oscillations, simultaneously measured. The phenomenon is theorized and used to establish the spatial map of the stray field. Based on our findings, we suggest integrating LJJs directly on the tips of cantilevers and using them as nanosensors of local magnetic fields in scanning probe microscopes. Such probes are less invasive than conventional magnetic MFM cantilevers and simpler to realize than SQUID-on-tip sensors.
由通过铜膜耦合的两个超导铌电极制成的横向约瑟夫森结（LJJ）被用于量化磁力显微镜（MFM）中使用的钴涂层悬臂的杂散磁场。磁性悬臂与LJJ的相互作用同时反映在LJJ的电子响应以及悬臂振荡的相移中。对该现象进行了理论分析，并用于建立杂散场的空间分布图。基于我们的发现，我们建议将LJJ直接集成在悬臂的尖端，并将它们用作扫描探针显微镜中局部磁场的纳米传感器。这种探针比传统的磁性MFM悬臂侵入性更小，并且比尖端超导量子干涉装置（SQUID）传感器更易于实现。
