Optical measurements were performed on thin films of RbxC60, identified by X-ray diffraction as mostly x=1 material. The samples were subjected to various heat treatments, including quenching and slow cooling from 400K. The dramatic increase in the transmission of the quenched samples, and the relaxation towards the transmission observed in slow cooled samples provides direct evidence for the existence of a metastable insulating phase. Slow cooling results in a phase transition between two electrically conducting phases.
@article{arxiv.cond-mat/9311060,
title = {Insulating and Conducting Phases of RbC60},
author = {Michael C. Martin and Daniel Koller and Xiaoqun Du and Peter W. Stephens and Laszlo Mihaly},
journal= {arXiv preprint arXiv:cond-mat/9311060},
year = {2009}
}
Comments
Minor revisions. Submitted to PRB, RevTeX 3.0 file, 2 postscript figures included, ir_dope