Abstract
Scanning nanoscale superconducting quantum interference devices (SQUIDs) are gaining interest as highly sensitive microscopic magnetic and thermal characterization tools of quantum and topological states of matter and devices. We introduce a technique of collimated differential-pressure magnetron sputtering for versatile self-aligned fabrication of SQUID-on-tip (SOT) nanodevices, which cannot be produced by conventional sputtering methods due to their diffusive, rather than the required directional point source, deposition. The technique provides access to a broad range of superconducting materials and alloys beyond the elemental superconductors employed in the existing thermal deposition methods, opening the route to greatly enhanced SOT characteristics and functionalities. Utilizing this method, we have developed molybdenum-rhenium (Mo66Re34) SOT devices with sub-50-nm diameter, magnetic flux sensitivity of 1.2 μφ0/Hz1/2 up to 3 T at 4.2 K, and thermal sensitivity better than 4 μK/Hz1/2 up to 5 T-about five times higher than any previous report-paving the way to nanoscale imaging of magnetic and spintronic phenomena and of dissipation mechanisms in previously inaccessible quantum states of matter.
| Original language | English |
|---|---|
| Article number | 044062 |
| Number of pages | 7 |
| Journal | Physical Review Applied |
| Volume | 12 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 28 Oct 2019 |
Bibliographical note
This work was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant No. 785971), by the US-Israel Binational Science Foundation (BSF) (Grant No. 2014155), by the Minerva Foundation with funding from the Federal German Ministry of Education and Research, and by the Leona M. and Harry B. Helmsley Charitable Trust Grant No. 2018PG-ISL006. E.Z. acknowledges the support by the Weston Nanophysics Challenge Fund.All Science Journal Classification (ASJC) codes
- General Physics and Astronomy