We present a new generation of a scanning MicroSQUID microscope operating in an inverted dilution refrigerator. The MicroSQUIDs have a size of 1.21μm\textsuperscript{2} and a magnetic flux sensitivity of 120 μΦ0/Hz and thus a field sensitivity of %550−6Φ0/Hz 550μG/Hz. The scan range at low temperatures is about 80 μm and a coarse displacement of 5 mm in x and y direction has been implemented. The MicroSQUID-to-sample distance is regulated using a tuning fork based force detection. A MicroSQUID-to-sample distance of 420 nm has been obtained. The reliable knowledge of this distance is necessary to obtain a trustworthy estimate of the absolute value of the superconducting penetration depth. An outlook will be given on the ongoing direction of development.
@article{arxiv.1403.5773,
title = {MicroSQUID Force microscopy in a dilution refrigerator},
author = {Danny Hykel and Zhao-Sheng Wang and Pauline Castellazzi and Thierry Crozes and Gorky Shaw and Klaus Hasselbach and K. F. Schuster},
journal= {arXiv preprint arXiv:1403.5773},
year = {2015}
}