Critical ultrasonics near the superfluid transition: finite-size effects
نویسندگان
چکیده
منابع مشابه
Critical Ultrasonics near the Superfluid Transition : Finite Size Effects
The suppression of order parameter fluctuations at the boundaries causes the ultrasonic attenuation near the superfluid transition to be lowered below the bulk value . We calculate explicitly the first deviation from the bulk value for temperatures above the lambda point . This deviation is significantly larger than for static quantities like the thermodynamic specific heat or other transport p...
متن کاملFinite-size Effects on the Thermal Resistivity of 4He Near the Superfluid Transition
We present measurements of the thermal resistivity ρ(t,L) (t ≡ T/Tλ − 1) near the superfluid transition temperature Tλ of 4He at saturated vapor pressure and confined in glass capillary arrays with rectangular capillary crosssections of spacing L = 1 μm, width w = 10μm, and length d # 1 mm. We expect the finite-size effect in this rectangular geometry to provide a good approximation to that in ...
متن کاملCritical Currents in Superfluid Helium Near T ,
The temperature dependence of the critical heat current Q, in He I1 has been measured in the temperature region 3. ("K) < T,-T< 1.2-("K). The result Qca(T,-~)1.07*0.01 is consistent with a divergent mutual friction near T, proposed recently by AHLERS. I. Introduction The resistanceless flow of superfluid helium is limited by critical relative velocities (v,-us), between its normal and superflui...
متن کاملCritical Fluctuation - Induced Thinning of 4 He Films near the Superfluid Transition
We report dielectric constant measurements showing critical fluctuation-induced thinning of 4He films near the superfluid transition. The films are adsorbed on a stack of copper electrodes suspended at different heights above bulk liquid. We calibrate the measurements by assuming that the film thickness away from the transition region at different heights is accurately given by theory. The thin...
متن کاملDissipation mechanisms near the superfluid 3He transition in aerogel.
We have investigated the dissipation (Q-1) using the torsion pendulum technique for pure 3He and 3He-4He mixtures in silica aerogel near the 3He superfluid transition (T(c)) in aerogel. With pure 3He the Q-1 decreases at the onset of superfluidity. When phase separated 3He-4He mixtures are introduced into the aerogel, the Q-1 does not decrease as rapidly and eventually increases for the highest...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Physics A: Mathematical and General
سال: 1998
ISSN: 0305-4470,1361-6447
DOI: 10.1088/0305-4470/31/34/001