Department of Magnetism and Phase Transformations
Head of the Department: Sergei V.Tarasenko, doctor of physicomathematical sciences, professor (062) 3110551
Directions of Scientific Researches: Analysis of energy structure, atomic properties in nonmetallic crystals under mega bar pressure. Investigation of superconducting and magnetic properties of S/Fbilayers and tunnel properties of SFIFStransitions (S – a superconductor, F – a ferromagnetic, I – a dielectric). Theory of localized and modulated structures in nanophase magnetic and liquidcrystalline media. Investigation of the role of relativistic mechanisms of a lateral interaction in the dynamics of multicomponent magnetic nanostructures. Optics and acoustics of magnetic photon and phonon crystals.
Basic Results
On the base of a cluster decomposition there was built up a pair interatomic potential of inert gases crystals the shortacting part of which was calculated from the first principles. It makes it possible to use it in analytical calculations of dielectric elastic properties, including the area of superhigh pressures.
Superconducting and magnetic properties of S/Fbilayers with a thin (less than a superconducting correlation length) ferromagnetic layer and the Josephson transitions on their base were first studied. There were predicted new effects: a) induced magnetism in the Slayer; b) inversion of the tunnel supercurrent sign at a parallel orientation of the Flayer magnetizations and c) critical current amplification at an antiparallel orientation of the Flayer magnetizations.
There has been created the theory of vortex and localized states in noncentrosymmetric magnetic and liquidcrystalline media.
There has been formulated a theoretical approach making possible to consecutively consider the role of a dynamic magnetoelastic interaction in the samples of finite dimensions at an optional quantity of a dimensionless parameter of a magnetoelastic bond. It allowed the determination of necessary conditions to form a number of new resonance and polarization anomalies in the dynamics of thin magnetic films and multilayer magnetic structures.
For the first time there was developed a selfcoordinating theory of the surface induced magnetic anisotropy and an antisymmetric interaction in nanostructures.
There has been proved an availability of a onetoone correspondence between a local geometry of the refraction surface of normal magnetic E, H and EHpolaritons of an unlimited crystal and a spectrum structure of this type of oscillations (both the surface and waveguide ones) in case of a thin film of this material. On this base there were predicted the unknown before anomalies in the dynamics of magnetic, segneto and magnetoelectrical films.
Applied researches Investigations in the field of physics and technology of the Josephson contacts and microcircuits, development of the microcircuit topology to register and calibrate electromagnetic signals on the base of the Josephson heterostructures. There has been developed a phenomenological theory of magnetic alloys possessing the form memory effect.
Scientific cooperation
Nowadays in the context of the program of scientific cooperation there are being conducted the joint investigations with the German (MaxPlanckInstitute for Mathematics in the Sciences, Leipzig), Indian (Department of Physics of the Indian Institute of Science, Bangalor), Russian (the Russian Academy of Sciences) scientists.
Selected publications
1. V.G.Bar'yakhtar, E.V.Zarochentsev, E.P.Troitskaya. Theory of adiabatic potential and atomic properties of metals. London. Ed. Gordon & Brich, 317, (2000).
2. V.V.Garkusha, V.N.Krivoruchko. Antiferromagnetic order and dielectric gap within the vortex core of antiferromagnetic superconduktor. J.Low Temp. Phys. 1 (139), 37 (2005).
3. D.L.Lyfar’, S.M.Ryabchenko, V.N.Krivoruchko, S.I.Khartsev, A.M.Grishin. Microwave absorption in a thin La_{0.7}Sr_{0.3}MnO_{3} film: Manifestation of colossal magnttoresistance. Phys. Rev. B 69, 100409 (2004).
4. V.N.Krivoruchko. Nanoskale superconductor – magnetic metal structures: critical current enhancement and proximity effect. J.Low Temp. Phys. 1 (139), 127 (2005). {International Conference “Functional Materials”. Oktober 611, 2003 Partenit, Crimea, Ukraine. Abstract AAL5 p.48 (Invited lecture).}
5. V.N.Krivoruchko. Magneticfieldinduced supercurrent enhancement in hybrid superconductor/magnet metal structures. Europhys.Lett. 3 (68), 447 (2004).
6. U.K.Röβler, A.N.Bogdanov. Magnetik states and reorientation transitions in antiferromagnetic superlattices. PRB 69, 69405 (2004).
7. A.N.Bogdanov, U.K.Röβler, M.Wolf, and K.H.Müller Magnetic structures and reorientation transitions in noncentrosymmetric uniaxial antiferromagnets Physical Review B 66, 214410 (2002).
8. S.V.Tarasenko. A new class of shift surface magnetsound waves in antiferromagnetic crystals. ZhETF 1, 663 (2002).
9. S.V.Tarasenko. A local geometry of an isofrequency surface and structure of the Lamb generalized waves in a limited segnetoelastic. ZhETF 119, 374 (2001).
10. V.G.Tarasenko, V.G.Shavrov. New mechanism of a surface magnetic polaritons in mag net with the linear magnetoelectric effect. Ferroelectrics 279, 3 (2002).
11. O.S. Tarasenko, S.V.Tarasenko, V.M.Yurchenko. Effect of a negative acoustic refraction in a onedimensional phonon crystal. ZhETF7 (80), 551 (2004).
