No abstract

No abstract

High-precision pressure measurements in solid 4 He, grown by the capillary blocking technique, have been made in temperatures range from 50 to 500 mK. The temperature dependence of pressure indicates that aside from the usual phonon contribution ϳT 4 , there is an additional contribution ϳT 2 , the latter becoming dominant at temperatures T Ͻ 300 mK, where an abnormal behavior attributed to supersolidity has been observed. The data suggest the appearance of a glassy phase ͑that might be responsible for the anomalous behaviors observed previously͒. A dramatic pressure decrease has been observed under annealing of the samples. The glassy contribution to the pressure can be eliminated in well-annealed crystals.

An experimental study of the electrical response in He4 in the temperature interval 1.5–Tλ is investigated experimentally by the torsion generator technique. It is shown that the motion of the normal component of He II, entrained by the wall of the torsion oscillator, causes dynamic polarization of the liquid. It is established that the induction potential is proportional to the square of the linear velocity of the oscillator wall.