2018/01/05 by Sachiko Nakamura, Daisuke Miyafuji, Ryo Toda +2
Physics and Astronomy · #cond-mat.mtrl-sci
paper · pdf · doi:10.1007/s10909-018-1983-3
published as Journal of Low Temperature Physics, Volume 192, Issue 5-6, pp. 330-345 (2018) · 15 pages, 13 figures, submitted to Journal of Low Temperature Physics. This is a split paper from arXiv:1704.03204v1
arxiv created 2018/01/05 · arxiv updated 2018/09/20
We have measured surface morphology and gas adsorption characteristics of uncompressed pyrolytic graphite sheet (uPGS) which is a candidate substrate for AC and DC superflow experiments on monolayers of 4He below T = 1 K. The PGS is a mass-produced thin graphite sheet with various thicknesses between 10 and 100 μm. We employed a variety of measuring techniques such as imagings with optical microscope, SEM and STM, Raman spectroscopy, and adsorption isotherm. PGS has smooth and atomically-flat external surfaces with high crystallinity. Although the specific surface area (<0.1 m2/g) is rather small, by making use of its smooth external surface, the thinnest uPGS of 10 μm thick is found to be suitable for the superflow experiments on the strictly two-dimensional helium systems.