Revealing the microscopic mechanism of elementary vortex pinning in superconductors

Vortex pinning is a crucial factor that determines the critical current of practical superconductors and enables their diverse applications. However, the underlying mechanism of vortex pinning has long been elusive, lacking a clear microscopic explanation. Here, using high-resolution scanning tunneling microscopy, we studied single vortex pinning induced by a point defect in layered FeSe-based superconductors. We found the defect-vortex interaction drives low-energy vortex bound states away from EF, creating a “mini” gap that effectively lowers the system energy and enhances pinning. By measuring the local density of states, we directly obtained the elementary pinning energy and estimated the pinning force via the spatial gradient of pinning energy. The results are consistent with bulk critical current measurement. Furthermore, we show that a general microscopic quantum model incorporating defect-vortex interaction can naturally capture our observation. It suggests that the local pairin..., The STM data was collected by the Nanonis and RHK STM controller software, and the transport data was collected by Quantum Design PPMS DynaCool system., , # Revealing the microscopic mechanism of vortex Pinning in superconductors

[https://doi.org/10.5061/dryad.1g1jwsv49](https://doi.org/10.5061/dryad.1g1jwsv49)

This dataset contains the raw data of this research, including the STM data and transport data presented in all the figures.

## Description of the data and file structure

The STM data are included in three types of files: SM4, 3ds, and sxm.

The SM4 files are generated by RHK R9 STM software and can be opened and proceeded by this software. However, RHK company does not provide a free version of this software now. Alternatively, the SM4 files can also be opened by Gwyddion, which is a free software and is now provided (to install, run “Gwyddion-2.65.win64.exe”).

The 3ds and sxm files are generated by Nanonis STM software. This software has a free version which is provided (to install, run “NanonisSTMSimulatorInstallerV5R6975.exe”). After installation, the 3ds file can be open by the “Binary File Inspector” module, and sxm file...,