Thermal conductivity and torsional oscillations of solid ⁴He
Polycrystalline samples of hcp ⁴He of molar volume Vm = 19.5 cm³ with small amount of ³He impurities
 were grown in an annular container by the blocked-capillary method. Three concentrations of ³He, x₃, were studied:
 isotopically purified ⁴He with the estimated x₃ < 10⁻¹⁰, co...
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| Published in: | Физика низких температур |
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| Date: | 2012 |
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| Format: | Article |
| Language: | English |
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Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України
2012
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| Online Access: | https://nasplib.isofts.kiev.ua/handle/123456789/117966 |
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| Journal Title: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Cite this: | Thermal conductivity and torsional oscillations
 of solid ⁴He/ M.Yu. Brazhnikov, D.E. Zmeev, A.I. Golov // Физика низких температур. — 2012. — Т. 38, № 11. — С. 1329–1335. — Бібліогр.: 29 назв. — англ. |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1862738392399216640 |
|---|---|
| author | Brazhnikov, M.Yu. Zmeev, D.E. Golov, A.I. |
| author_facet | Brazhnikov, M.Yu. Zmeev, D.E. Golov, A.I. |
| citation_txt | Thermal conductivity and torsional oscillations
 of solid ⁴He/ M.Yu. Brazhnikov, D.E. Zmeev, A.I. Golov // Физика низких температур. — 2012. — Т. 38, № 11. — С. 1329–1335. — Бібліогр.: 29 назв. — англ. |
| collection | DSpace DC |
| container_title | Физика низких температур |
| description | Polycrystalline samples of hcp ⁴He of molar volume Vm = 19.5 cm³ with small amount of ³He impurities
were grown in an annular container by the blocked-capillary method. Three concentrations of ³He, x₃, were studied:
isotopically purified ⁴He with the estimated x₃ < 10⁻¹⁰, commercial ‘well-grade’ helium with x₃ ~ 3⋅10⁻⁷ and
a mixture with x₃ = 2.5⋅10⁻⁶. Torsional oscillations at two frequencies, 132.5 and 853.6 Hz, and thermal conductivity
were investigated before and after annealing. The solid helium under investigation was located not only in
the annular container but also in the axial fill line inside two torsion rods and dummy bob of the doublefrequency
torsional oscillator. The analysis of the frequency shifts upon loading with helium and changing temperatures
of different parts of the oscillator suggests that the three techniques probe the properties of solid helium
in three different locations: the two different torsion modes respond to the changes of the shear modulus of solid
helium in either of the two torsion rods while the thermal conductivity probes the phonon mean free path in solid
helium inside the annular container. The temperature and width of the torsional anomaly increase with increasing
frequency and x₃. The phonon mean free path increases with increasing x3. Annealing typically resulted in an increased
phonon mean free path but often in little change in the torsional oscillator response. While the magnitude
of the torsional anomaly and phonon mean free path can be very different in different samples, no correlation
was found between them.
|
| first_indexed | 2025-12-07T20:03:50Z |
| format | Article |
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| id | nasplib_isofts_kiev_ua-123456789-117966 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 0132-6414 |
| language | English |
| last_indexed | 2025-12-07T20:03:50Z |
| publishDate | 2012 |
| publisher | Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України |
| record_format | dspace |
| spelling | Brazhnikov, M.Yu. Zmeev, D.E. Golov, A.I. 2017-05-27T18:20:52Z 2017-05-27T18:20:52Z 2012 Thermal conductivity and torsional oscillations
 of solid ⁴He/ M.Yu. Brazhnikov, D.E. Zmeev, A.I. Golov // Физика низких температур. — 2012. — Т. 38, № 11. — С. 1329–1335. — Бібліогр.: 29 назв. — англ. 0132-6414 PACS: 67.80.bd, 65.40.–b https://nasplib.isofts.kiev.ua/handle/123456789/117966 Polycrystalline samples of hcp ⁴He of molar volume Vm = 19.5 cm³ with small amount of ³He impurities
 were grown in an annular container by the blocked-capillary method. Three concentrations of ³He, x₃, were studied:
 isotopically purified ⁴He with the estimated x₃ < 10⁻¹⁰, commercial ‘well-grade’ helium with x₃ ~ 3⋅10⁻⁷ and
 a mixture with x₃ = 2.5⋅10⁻⁶. Torsional oscillations at two frequencies, 132.5 and 853.6 Hz, and thermal conductivity
 were investigated before and after annealing. The solid helium under investigation was located not only in
 the annular container but also in the axial fill line inside two torsion rods and dummy bob of the doublefrequency
 torsional oscillator. The analysis of the frequency shifts upon loading with helium and changing temperatures
 of different parts of the oscillator suggests that the three techniques probe the properties of solid helium
 in three different locations: the two different torsion modes respond to the changes of the shear modulus of solid
 helium in either of the two torsion rods while the thermal conductivity probes the phonon mean free path in solid
 helium inside the annular container. The temperature and width of the torsional anomaly increase with increasing
 frequency and x₃. The phonon mean free path increases with increasing x3. Annealing typically resulted in an increased
 phonon mean free path but often in little change in the torsional oscillator response. While the magnitude
 of the torsional anomaly and phonon mean free path can be very different in different samples, no correlation
 was found between them. We thank P.V.E. McClintock for providing isotopically
 purified ⁴He, and R. Schanen for his contribution at the
 preparatory stage of the experiment, R. Schanen for his
 contribution at the preparatory stage of the experiment, and
 S. Gillot and M. Sellers for building the TO cell. This work
 was supported by the Engineering and Physical Sciences
 Research Council [grant number EP/H014691]. en Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України Физика низких температур К 75-летию Л.П. Межова-Деглина Thermal conductivity and torsional oscillations of solid ⁴He Article published earlier |
| spellingShingle | Thermal conductivity and torsional oscillations of solid ⁴He Brazhnikov, M.Yu. Zmeev, D.E. Golov, A.I. К 75-летию Л.П. Межова-Деглина |
| title | Thermal conductivity and torsional oscillations of solid ⁴He |
| title_full | Thermal conductivity and torsional oscillations of solid ⁴He |
| title_fullStr | Thermal conductivity and torsional oscillations of solid ⁴He |
| title_full_unstemmed | Thermal conductivity and torsional oscillations of solid ⁴He |
| title_short | Thermal conductivity and torsional oscillations of solid ⁴He |
| title_sort | thermal conductivity and torsional oscillations of solid ⁴he |
| topic | К 75-летию Л.П. Межова-Деглина |
| topic_facet | К 75-летию Л.П. Межова-Деглина |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/117966 |
| work_keys_str_mv | AT brazhnikovmyu thermalconductivityandtorsionaloscillationsofsolid4he AT zmeevde thermalconductivityandtorsionaloscillationsofsolid4he AT golovai thermalconductivityandtorsionaloscillationsofsolid4he |