Gg. Sergeeva, ATTENUATION OF LOW-FREQUENCY ACOUSTIC ENERGY IN BI-BASED SUPERCONDUCTORS, Low temperature physics (Woodbury, N.Y.), 24(10), 1998, pp. 757-759
The attenuation of low-frequency acoustic energy in stripes of the low
-temperature tetragonal phase of Bi-2212 ceramics is studied taking in
to account the d(x2-y2)-symmetry of the superconducting order paramete
r (SOP) and the dynamic analog of phase separation. The contribution t
o the energy density of the strain-order parameter coupling leads to a
finite value of attenuation in superconductors with a peculiar SOP. T
he frequency and temperature dependences of attenuation are analyzed a
nd compared with the available experimental results. It is shown that
these data are an indirect evidence of the SOP symmetry: the d(x2-y2)-
symmetry for the Bi-2212 phase and the s-symmetry for the Bi-2223 phas
e. The existence of an ordered low-temperature state responsible for t
he low-frequency attenuation peak and other anomalies in the propertie
s of Bi-based ceramics in the temperature range 20-40 K is proposed. (
C) 1998 American Institute of Physics. [S1063-777X(98)01110-4]