Experimental verification of contact-size estimates in point-contact spectroscopy on superconductor/ferromagnet heterocontacts

TL;DR

This study experimentally verifies the accuracy of contact-size estimates in point-contact spectroscopy on superconductor/ferromagnet heterocontacts by comparing SEM measurements with theoretical models, emphasizing the importance of careful local parameter characterization.

Contribution

It provides experimental validation for contact-size estimation methods in superconductor/ferromagnet heterocontacts using SEM measurements and theoretical comparisons.

Findings

Size estimates are reasonable with careful local parameter characterization.

Direct SEM measurements align with theoretical models for contact size.

Accurate contact size estimation depends on detailed sample characterization.

Abstract

Nanostructured superconductor/ferromagnet heterocontacts are studied in the different transport regimes of point-contact spectroscopy. Direct measurements of the nanocontact size by scanning electron microscopy allow a comparison with theoretical models for contact-size estimates of heterocontacts. Our experimental data give evidence that size estimates yield reasonable values for the point-contact diameter $d$ as long as the samples are carefully characterized with respect to the local electronic parameters.