Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He
We report thermal conductivity measurements of porous Vycor glass when it is empty and when the pores are filled with helium between 0.06 and 0.5 K. The filling of liquid ^3 He and liquid ^4 He inside the Vycor pores brings about two to three-fold reduction of the thermal conductivity as compared wi...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2013-01-01
|
| Series: | New Journal of Physics |
| Online Access: | https://doi.org/10.1088/1367-2630/15/6/063030 |
| _version_ | 1797751596543639552 |
|---|---|
| author | Z G Cheng M H W Chan |
| author_facet | Z G Cheng M H W Chan |
| author_sort | Z G Cheng |
| collection | DOAJ |
| description | We report thermal conductivity measurements of porous Vycor glass when it is empty and when the pores are filled with helium between 0.06 and 0.5 K. The filling of liquid ^3 He and liquid ^4 He inside the Vycor pores brings about two to three-fold reduction of the thermal conductivity as compared with empty Vycor. This dramatic reduction of thermal conductivity, not seen with solid ^3 He and ^4 He in the pores, is the consequence of hydrodynamic sound modes in liquid helium that greatly facilitate the quantum tunneling of the two-level systems in Vycor and enhance the scattering of the thermal phonons in the silica network. |
| first_indexed | 2024-03-12T16:50:50Z |
| format | Article |
| id | doaj.art-a4d79c12237e42e0bc7e0499268c564b |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:50:50Z |
| publishDate | 2013-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-a4d79c12237e42e0bc7e0499268c564b2023-08-08T11:11:02ZengIOP PublishingNew Journal of Physics1367-26302013-01-0115606303010.1088/1367-2630/15/6/063030Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4HeZ G Cheng0M H W Chan1Department of Physics, The Pennsylvania State University , University Park, PA 16802, USADepartment of Physics, The Pennsylvania State University , University Park, PA 16802, USAWe report thermal conductivity measurements of porous Vycor glass when it is empty and when the pores are filled with helium between 0.06 and 0.5 K. The filling of liquid ^3 He and liquid ^4 He inside the Vycor pores brings about two to three-fold reduction of the thermal conductivity as compared with empty Vycor. This dramatic reduction of thermal conductivity, not seen with solid ^3 He and ^4 He in the pores, is the consequence of hydrodynamic sound modes in liquid helium that greatly facilitate the quantum tunneling of the two-level systems in Vycor and enhance the scattering of the thermal phonons in the silica network.https://doi.org/10.1088/1367-2630/15/6/063030 |
| spellingShingle | Z G Cheng M H W Chan Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He New Journal of Physics |
| title | Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He |
| title_full | Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He |
| title_fullStr | Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He |
| title_full_unstemmed | Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He |
| title_short | Threefold reduction in thermal conductivity of Vycor glass due to adsorption of liquid 4He |
| title_sort | threefold reduction in thermal conductivity of vycor glass due to adsorption of liquid 4he |
| url | https://doi.org/10.1088/1367-2630/15/6/063030 |
| work_keys_str_mv | AT zgcheng threefoldreductioninthermalconductivityofvycorglassduetoadsorptionofliquid4he AT mhwchan threefoldreductioninthermalconductivityofvycorglassduetoadsorptionofliquid4he |