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Abstracts
P4.18
Measurement of the complex permittivity of liquid He-4 in
millimeters wave range by ”whispering gallery” mode resonator
A.V. Smorodin(1), A.S. Rybalko(2) and D. Konstantinov(1).
1) Okinawa Institute of Science and Technology, Tancha 1919-1, Okinawa
904-0412, Japan
2) B.Verkin Institute for Low Temperature Physics and Engineering, Prospekt
Nauky 47, Kharkiv 61103, Ukraine
We report an experimental study of electrical properties of liquid helium 4 in
temperature range 1.2-3 K. The complex permittivity of He4 was determined
using a ”whispering gallery” resonator. Using the resonant perturbation method
the complex permittivity of liquid He4 is extracted. Our result is consistent with
theoretical and experimental works by other authors. We also discuss effect of
doubling of the ”whispering gallery” modes propagating in the cavity.
P4.19
Adiabatic melting experiment: status and prospects.
A.P. Sebedash*, J.T. Touriniemi
Aalto University, School of Science, Applied Physics Department. PO BOX
15100, 00076 AALTO, FINLAND
*P.L. Kapitza Institute for Physical Problems, RAS, ul. Kosygina 2, Moscow,
119334, Russia
We describe our ongoing experiment, aiming to cool saturated helium mixtures
to ultra-low temperatures, into tens of microKelvins regime. Previously we
demonstrated physical principle of cooling at temperatures well below of superfluid
transition of concentrated phase, pure
3
He (JLTP,81, p.725 (2007)). We describe
improvements made to protect system from irreversibility appearing owing to
higher temperature surroundings, and to practical realization of the method.
Results of testing different systems at low temperatures are presented and
discussed.
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