Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Feb 7;12(5):3174-3182.
doi: 10.1039/c9nr08578e. Epub 2020 Jan 22.

SQUID-on-tip With Single-Electron Spin Sensitivity for High-Field and Ultra-Low Temperature Nanomagnetic Imaging

Affiliations

SQUID-on-tip With Single-Electron Spin Sensitivity for High-Field and Ultra-Low Temperature Nanomagnetic Imaging

Y Anahory et al. Nanoscale. .

Abstract

Scanning nanoscale superconducting quantum interference devices (nanoSQUIDs) are of growing interest for highly sensitive quantitative imaging of magnetic, spintronic, and transport properties of low-dimensional systems. Utilizing specifically designed grooved quartz capillaries pulled into a sharp pipette, we have fabricated the smallest SQUID-on-tip (SOT) devices with effective diameters down to 39 nm. Integration of a resistive shunt in close proximity to the pipette apex combined with self-aligned deposition of In and Sn, has resulted in SOTs with a flux noise of 42 nΦ0 Hz-1/2, yielding a record low spin noise of 0.29 μB Hz-1/2. In addition, the new SOTs function at sub-Kelvin temperatures and in high magnetic fields of over 2.5 T. Integrating the SOTs into a scanning probe microscope allowed us to image the stray field of a single Fe3O4 nanocube at 300 mK. Our results show that the easy magnetization axis direction undergoes a transition from the 〈111〉 direction at room temperature to an in-plane orientation, which could be attributed to the Verwey phase transition in Fe3O4.

Similar articles

See all similar articles

LinkOut - more resources

Feedback