Dataset for "The Search for Spontaneous Edge Currents in Sr2RuO4 Mesa Structures with Controlled Geometrical Shapes"

Data collection method:

The primary datasets are scanning Hall microscopy (SHM) images. These have been captured with a modified low-temperature scanning tunnelling microscope (STM) where the tunnelling tip has been replaced by a custom-fabricated semiconductor chip. The Hall probe is patterned in the two-dimensional electron gas of a GaAs/AlGaAs heterostructure, defined by the intersection of two 800 nm wide wires situated about 5 micrometres from the Au-coated corner of a deep mesa etch that acts as an integrated STM tip. The Hall probe is mounted at an angle of about 1 degree with respect to the sample plane, with the STM tip being the closest point to the sample surface. In operation the sample is first approached towards the sensor until tunnelling is established and then retracted about 100 nm for rapid ‘flying mode’ scanning with the active Hall probe about 200 nm above the sample and a spatial resolution of about 800 nm. In this way quantitative maps of the z-component of magnetic induction can be captured non-invasively. Images shown in this manuscript have been captured in the range T= 0.3-1.6 K when the full scan range of our piezotube is approximately 14 µm × 14 µm.

Data processing and preparation activities:

With the exception of images shown in Figure 4 the SHM data in the archive are raw as-captured data without any post-processing.

Technical details and requirements:

Data captured using bespoke Nanomagnetics Instruments imaging software.

Additional information:

The SHM image datasets are formatted as the magnetic induction in Gauss measured at each point on a 128 × 128 array of pixel positions (corresponding to the spatial location of the Hall sensor in the plane parallel to the sample). At a measurement temperature in the range T= 0.3-1.6 K this corresponds to a scan range of approximately14 µm × 14 µm.