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TC Chui

Publications and source records attributed to TC Chui.

9 recordsLinked to original sources
PubMed2000

Specific heat of helium confined to a 57- &mgr;m planar geometry near the lambda point

We report measurements of the specific heat of liquid helium confined to 57-&mgr;m planar gaps extending to within a few nanokelvin of the bulk lambda transition. The data are in fair agreement with Monte Carlo estimates for finite-size effects and with renormalization-group-theory predictions above the transition. Far from the transition, we find surface specific heat exponents, alpha(s) = 0.64+/-0.05 below, and 0.65+/-0.2 above, which compare well with the prediction of 0.658. Comparison with other recent data on small length scales shows some areas of agreement.

Journal Article↗
PubMed2000

Enhanced heat capacity and a new temperature instability in superfluid 4He in the presence of a constant heat flux near t(lambda)

We present the first experimental evidence that the heat capacity of superfluid 4He, at temperatures very close to the lambda point T(lambda), is enhanced by a constant heat flux Q. The heat capacity at constant Q, C(Q), is predicted to diverge at a temperature T(c)(Q)<T(lambda) at which superflow becomes unstable. In agreement with previous measurements, we find that dissipation enters our cell at a temperature, T(DAS)(Q), below the theoretical value, T(c)(Q). We argue that T(DAS)(Q) can be accounted for by a temperature instability at the cell wall, and is therefore distinct from T(c)(Q). The excess heat capacity we measure has the predicted scaling behavior as a function of T and Q, but it is much larger than predicted by current theory.

Journal Article↗