Behavior of quartz forks oscillating in isotopically pure He-4 in the T -> 0 limit

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F12%3A10130470" target="_blank" >RIV/00216208:11320/12:10130470 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1103/PhysRevB.85.144518" target="_blank" >http://dx.doi.org/10.1103/PhysRevB.85.144518</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.85.144518" target="_blank" >10.1103/PhysRevB.85.144518</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Behavior of quartz forks oscillating in isotopically pure He-4 in the T -> 0 limit

Popis výsledku v původním jazyce

We report that at low drives, the resonant frequencies and linewidths of nominally 32-kHz quartz tuning forks oscillating in isotopically pure superfluid He-4 at similar to 10 mK are dependent on the dimensions of their environment. We confirm the importance of coupling between forks and acoustic modes within the cell, and develop a theory of their coupled dynamics to account for the observations. The frequencies and linewidths are reproducible on a time scale of tens of minutes, but pronounced drifts are seen over longer intervals. We suggest that the drifts are attributable to changes in the velocity of sound due to tiny pressure changes. In studies at high drives, we observe two critical velocities: v(c1) approximate to 0.6 cm/s, where the drag mayeither increase or decrease, depending on the linewidth; and v(c2) approximate to 10 cm/s, above which there seems to be fully turbulent flow. At high drives, the behavior of the drag differs markedly between forks that appear otherwise t

Název v anglickém jazyce

Behavior of quartz forks oscillating in isotopically pure He-4 in the T -> 0 limit

Popis výsledku anglicky

We report that at low drives, the resonant frequencies and linewidths of nominally 32-kHz quartz tuning forks oscillating in isotopically pure superfluid He-4 at similar to 10 mK are dependent on the dimensions of their environment. We confirm the importance of coupling between forks and acoustic modes within the cell, and develop a theory of their coupled dynamics to account for the observations. The frequencies and linewidths are reproducible on a time scale of tens of minutes, but pronounced drifts are seen over longer intervals. We suggest that the drifts are attributable to changes in the velocity of sound due to tiny pressure changes. In studies at high drives, we observe two critical velocities: v(c1) approximate to 0.6 cm/s, where the drag mayeither increase or decrease, depending on the linewidth; and v(c2) approximate to 10 cm/s, above which there seems to be fully turbulent flow. At high drives, the behavior of the drag differs markedly between forks that appear otherwise t

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BK - Mechanika tekutin

OECD FORD obor

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Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2012

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review B - Condensed Matter and Materials Physics

ISSN

1098-0121

e-ISSN

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Svazek periodika

85

Číslo periodika v rámci svazku

14

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

13

Strana od-do

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Kód UT WoS článku

000302958900002

EID výsledku v databázi Scopus

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