Critical Ultrasonics near the Superfluid Transition : Finite Size Effects
نویسندگان
چکیده
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 properties like the thermal conductivity . This makes ultrasonics a very effective probe for finite size effects . PACS number(s): 64.60.Ht
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