Formation of a disordered phase in deformed solid [sup.4]He in the region of supersolid state

• Published in: Journal of experimental and theoretical physics Vol. 111; no. 4; pp. 619 - 1237
• Main Authors: Degtyarev, I.A, Lisunov, A.A, Maidanov, V.A, Rubanskiy, V.Yu, Rubets, S.P, Rudavskii, E. Ya, Rybalko, A.S, Tikhii, V.A
• Format: Journal Article
• Language: English
• Published: United States Springer 01.10.2010
• Subjects: ANNEALING; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTAL DEFECTS; CRYSTAL STRUCTURE; CRYSTALS; DEFORMATION; DISLOCATIONS; ELEMENTS; EVEN-EVEN NUCLEI; FLUIDS; GASES; HEAT TREATMENTS; HELIUM; HELIUM 4; HELIUM ISOTOPES; ISOTOPES; LIGHT NUCLEI; LINE DEFECTS; NONMETALS; NUCLEI; PHONONS; PRESSURE DEPENDENCE; QUASI PARTICLES; RARE GASES; RELAXATION; SOLIDS; STABLE ISOTOPES; TEMPERATURE DEPENDENCE; TUNNEL EFFECT
• ISSN: 1063-7761; 1090-6509
• DOI: 10.1134/S1063776110100122

A method has been proposed to create disorder in helium crystals by their deformation immediately during the experiment. Precise measurements of the pressure have been performed at a constant volume in samples of various qualities. It has been revealed that excess pressure, which is characterized by the quadratic temperature dependence typical of the disordered glassy phase and of the dislocation contribution to the pressure, is observed in the deformed crystals along with the phonon contribution to the pressure. The effect is observed in the supersolid-state region and disappears after the careful annealing of the crystals. The ultraslow relaxation of the pressure also characteristic of the glassy phase has been observed in the process of annealing of the crystals. The obtained experimental results have been analyzed in the framework of the dislocation model and the model of two-level tunneling states.