Head of the Department: Fil' Vyacheslav Dmitrievich
tel: +(380)-57-341-08-71
fax: +(380)-57-340-33-70
E-mail: fil@ilt.kharkov.ua
The Department was founded in 1961 with an active participation of A.A.Galkin, Academician of the National Academy of Science of Ukraine.
In the period from 1961 to 1984 the Department was headed by P.A.Bezugly, Candidate of Science (Phys. and Math.). Since then it has been headed by V.D.Fil', Doctor of Science (Phys. and Math.).
At present the Department is fifteen in number, including two Doctors of Science (V.D.Fil', F.F.Mende) and four Candidates of Science ( N.G.Burma, A.L.Gaiduk, S.V.Zherlitsyn, A.M.Stepanenko ).
The Department is involved in the studies by the following
lines:
electronic properties of metals (superconductors included);
magnetoelastic properties of magnetic dielectrics;
acoustic characteristics of HTSC materials and related compounds;
interaction between sound and two-level systems in metal glasses.
Besides, the investigations are being conducted to find the reasons for emerging of charge in a superconductor with high-density electric current.
Among the most interesting results are as follows:
measurement of energy gap anisotropy in traditional
superconductors (In, Al);
detection of giant (~10%) electronic renormalization of elastic
moduli in metals at high magnetic fields;
examination of variations in sound velocity under superconducting
transition;
observation of electronic transfer of sound;
observation of nonlinear acoustic effects of electron origin in
normal metals and superconductors;
finding of zero-sound in metal;
observation of anomalous (not followed from the theory of
elasticity) angular dependences of sound velocity in Nd(Pr)2CuO4 single
crystals indirectly suggestive of the existence of additional
planar vibrational modes in these objects. Moreover, all the components
of elasticity moduli tensors in La2CuO4, Nd2CuO4
and Pr2CuO4 single crystals have been
measured with an accuracy permitting the use of the results as
reference data.
The techniques developed at the Department make it possible to measure relative variations in sound velocity to not worse than 10- 5 - 10-6 as well as sound attenuation 10- 3 in fields up to 4T at temperatures between 0,4 and 300 K. A method for measuring absolute values of sound velocity with an accuracy of 0,1 to 1% has been developed for highly absorbing inhomogeneous samples for which the conventional techniques of measuring sound velocity fail. The Department has x-ray equipments used to certify the samples under investigation.
The Department works in close cooperation with W.Trzebiatowski Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Wroclaw, Poland and Institute of Physics, I.W. Goethe University, Frankfurt on Main, Germany.