"Magnetoscan": A Modified Hall Probe Scanning Technique for the Detection of Inhomogeneities in Bulk High Temperature Superconductors

TL;DR

The paper introduces 'Magnetoscan', a new method using a small permanent magnet during Hall probe scans to detect local inhomogeneities in bulk high-temperature superconductors, providing qualitative insights into surface shielding currents.

Contribution

It presents a novel scanning technique that locally magnetizes samples during measurement, improving detection of inhomogeneities in superconductors.

Findings

Effective detection of local inhomogeneities in superconductors.

Provides qualitative mapping of surface shielding currents.

Enhances resolution over traditional Hall probe scanning methods.

Abstract

We present a novel technique for the investigation of local variations of the critical current density in large bulk superconductors. In contrast to the usual Hall probe scanning technique, the sample is not magnetized as a whole before the scan, but locally by a small permanent magnet, which is fixed near the Hall probe, during the scanning process. The resulting signal can be interpreted as a qualitative measure of the local shielding currents flowing at the surface.