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arXiv · 1610.00433

Design and testing of low temperature part of an UHV SPM microscope

Jiri Frolec·Jakub Vonka·Pavel Hanzelka·Tomas Kralik·Vera Musilova·Pavel Urban
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Abstract

We have developed low temperature part of an ultra high vacuum scanning probe microscope (UHV-SPM) working at variable temperature within the range from 20 K to 700 K. To achieve the required temperature range, a flow cooling system using cryogenic helium (~5 K) as a coolant was designed. The system consists of a flow cryostat and a flexible low-loss transfer line connecting a Dewar vessel with the flow cryostat. We have also tested liquid nitrogen (~ 77 K) as an alternative low-cost coolant. Using nitrogen, the microscope can operate at temperatures of about 100 K and higher. As the flow of the coolant through the cryostat can cause thermally induced two-phase flow fluctuations resulting in instability in temperatures, preliminary tests were done in order to find ways of avoiding the temperature oscillations and optimising the cooling process.

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Jiri Frolec, Jakub Vonka, Pavel Hanzelka, Tomas Kralik, Vera Musilova, Pavel Urban. 2016-10-03. Design and testing of low temperature part of an UHV SPM microscope. https://arxiv.org/abs/1610.00433

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