Using scanning tunnelling microscopy at 400mK, we have obtained maps of around 100 vortices in SnMo6S8 from 2 - 9T. The orientational and positional disorder at 5 and 9T show that these are the first large-scale images of a vortex glass. At higher temperature a magnetisation peak effect is observed, whose upper boundary coincides with a lambda anomaly in the specific heat. Our data favour a kinetic glass description of the vortex melting transition, indicating that vortex topological disorder persists at fields and temperatures far below the peak effect in low-Tc superconductors.
@article{arxiv.0903.2389,
title = {Real-space vortex glass imaging and the vortex phase diagram of SnMo6S8},
author = {A. P. Petrovic and Y. Fasano and R. Lortz and C. Senatore and A. Demuer and A. B. Antunes and A. Paré and D. Salloum and P. Gougeon and M. Potel and Ø. Fischer},
journal= {arXiv preprint arXiv:0903.2389},
year = {2013}
}