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arXiv · 1801.01721

Pyrolytic Graphite Sheet, a New Adsorption Substrate for Superfluid Thin Films

Sachiko Nakamura·Daisuke Miyafuji·Ryo Toda·Tomohiro Matsui·Hiroshi Fukuyama
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Abstract

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 {\mu}m. 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 m$^2$/g) is rather small, by making use of its smooth external surface, the thinnest uPGS of 10 {\mu}m thick is found to be suitable for the superflow experiments on the strictly two-dimensional helium systems.

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Sachiko Nakamura, Daisuke Miyafuji, Ryo Toda, Tomohiro Matsui, Hiroshi Fukuyama. 2018-01-05. Pyrolytic Graphite Sheet, a New Adsorption Substrate for Superfluid Thin Films. https://doi.org/10.1007/s10909-018-1983-3

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