Sergei Shevchenko - Leading
Researcher.
Graduated from Kharkov Polytechnical
Institute in 1964.
PhD Phys & Math (1970); DSc Phys & Math
(1993).
Since 1971 has worked at ILTPE as a junior researcher, senior researcher
(1976-1995), from 1995 – leading researcher. 1985 – 1995 –> professor
at Kharkov State University; since 1995 – professor at Kharkov
Polytechnical University.
Research areas:
Excitonic Superfluidity in Multilayer
Electron Systems
The possibility of superfluidity in the
systems with pairing of spatially separated carriers (SPSSC) in zero
magnetic field was predicted by Shevchenko in 1976. Recent results
obtained in this direction are as follows. It is shown that in SPSSC the
quantum vortices can be induced by non-uniform magnetic and electric
fields with nonzero two-dimensional divergence. The vortex patterns at
certain field configurations are found. (Shevchenko, 1997, 2000). It is
established that in strong magnetic fields the vortices have an electric
charge of order of the electron charge (Shevchenko, 2003). States with
interlayer phase coherence in multilayer quantum Hall systems are
studied. It is shown the phase coherence emerges only in separate
bilayer complexes, and there is no coherence between the layers
belonging to different complexes. The conditions of stability of the
phase coherent state relative to a transition to the charge ordered
state are established. (Bezuglyj, Shevchenko, 2000; Shevchenko, Fil,
Yakovleva, 2004). A new mechanism of binding of two equally charged
carriers in double layer systems in a magnetic field of special form
(magnetic fields in adjacent layer are equal in magnitude and opposite
in direction) is proposed. (Shevchenko, Vol, 2003).
Interlayer tunnel conductivity of n-p
bilayers with the electron-hole pairs in the Bose-Einstein condensed
state was studied. A mechanism that explains a zero bias peak anomaly
observed recently in bilayer quantum Hall systems is proposed.
(Bezuglyj, Shevchenko, 2004).
Bose-Einstein Condensation
The Bogolyubov-de-Gennes equations for a
two-dimensional Bose gas are derived. (Shevchenko, 1992). The exact
solutions for the spectrum and eigenfunctions of elementary excitations
in Bose gas in external potentials of special forms are found. (Fil,
Shevchenko, 2001). The nondissipative drag in bilayer Bose systems is
studied (Shevchenko, Terentjev, 1999).
Selected publications:
- S. I. Shevchenko, Theory of superconductivity in the systems
with pairing of spatially separated electrons and holes. FNT
2, 505 (1976).
- S. I. Shevchenko, On the Theory of a Bose Gas in a Nonuniform
Field, FNT 18, 328 (1992).
- S. I. Shevchenko, Polarizable Quantum Systems in Crossed
Electric and Magnetic Fields, Phys. Rev. Lett. 75, 3312 (1995).
- S. I. Shevchenko, Vortices and Vortical Structures in Systems
with Pairing of Spatially Separated Electrons and Holes, PR B 56,
10355-10368 (1997),
- S. V. Terentjev, S.I. Shevchenko, On Transfer of Motion in a
System of Two-Dimensional Superfluid Bose-Gases Separated by a Thin
Layer, Low Temp. Phys. 25, 493 (1999).
- V. A. Bezugly, S.I.Shevchenko, Spontaneous Interlayer Coherence
in Multilayer Electron Systems in Strong Magnetic Fields, Physica B,
284-288, 1205 (2000).
- S. I. Shevchenko, On Vortices Induced in Superfluid Films by
Crossed Electric and Magnetic Fileds, J. Low Temp. Phys. 121, 429
(2000).
- D. V. Fil, S. I. Shevchenko, Collective Excitations of a
Two-Dimensional Interacting Bose Gas in External Fields, Phys. Rev.
A 64, 013607 (2001).
- S. I. Shevchenko, E. D. Vol, Metastable Bound State of a Pair of
Two-Dimensional Spatially Separated Electrons in Anti-Parallel
Magnetic Fields, J. Phys.: Condens. Matter, 15, 8455 (2003).
- S. I. Shevchenko, Charged Vortices in Superfluid Systems with
Pairing of Spatially Separated Carriers, Phys. Rev. B 67, 214515
(2003).
- A. I. Bezuglyj, S. I. Shevchenko, Order Parameter Phase Locking
as a Cause of a Zero Bias Peak in the Differential Tunneling
Conductance of Bilayers with Electron-Hole Pairing, Low Temp. Phys.
30, 208 (2004).
- S. I. Shevchenko, D. V. Fil, A. A. Yakovleva, Charge Ordering
and Interlayer Phase Coherence in Quantum Hall Superlattices, Low
Temp. Phys. 30, 321 (2004).
- A. I. Bezuglyj, S. I. Shevchenko, Polarizable Quantum Systems in
Crossed Electric and Magnetic Fields, Phys. Rev. B 75, 075322
(2007).
- S. I. Shevchenko, A. S. Rukin, On the electrical activity of
superfluid systems, JETP Letters 90, 42 (2009).
- A. I. Bezuglyj and S. I. Shevchenko, Oscillations of an
electron–hole pair condensate in excitonic traps, Low Temp.
Phys. 35, 373 (2009).
- S. I. Shevchenko and A. S. Rukin, On electrical phenomena in
electroneutral superfluid systems, Low Temp. Phys. 36, 146 (2010).
- S. I. Shevchenko and A. S. Rukin, On the electric polarization
of inhomogeneous superfluid systems, Low Temp. Phys. 36, 596 (2010).
- A. S. Rukin and S. I. Shevchenko, On electric fields created by
quantized vortices, Low Temp. Phys. 37, 884
(2011).
- S. I. Shevchenko and A. S. Rukin, Two approaches to the
description of dilute superfluid Bose
systems, Low Temp. Phys. 38, 905 (2012).
- S. I. Shevchenko, On the possibility of vortex creation in
superfluid systems by crossed homogeneous magnetic and inhomogeneous
electric fields, Low Temp. Phys. 39, 319 (2013).
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