Current Research Projects

 The central aspect which I consider in the modelling of the electronic properties of
high-Tc cuprates, is their inhomogeneous nature. 
The inhomogeneous electronic scenario (phase separation) implies that
the surfaces are composed of a mixture of  microscopic ordered and uniform disordered
islands.  The spectral properties of such an electronic inhomogeneous state provide
natural explanation for low-energy nodal ARPES kink-like features and exhibit
novel non-Fermi-liquid state stabilized through electron-phonon coupling.

Here are the latest results:
N.Pavlenko and T.Kopp,  Electron-phonon coupling in a two-dimensional inhomogeneous electron gas
arXiv/0708.3588

The goal of this project is theoretical engineering of superconducting field effect devices
where a shift of superconducting Tc can be achieved by electrostatical doping. 
In this work, two complementary approaches are combined:

  1. DFT-studies of electronic structure at interfaces between high-Tc cuprates and
            perovskite oxides like SrTiO3 typically employed as dielectric gates.
            Here our recent results: N.Pavlenko, I.Elfimov, T.Kopp, and G.A.Sawatzky,
                                                      Interface hole doping in cuprate-titanate superlattices PRB 75, 140512(R) (2007) (cond-mat/0605589)

  2.  Effective Hamiltonian modeling of physics at interfaces between superconducting cuprates and dielectric perovskites
            Here the recent results:
                         N.Pavlenko and T.Kopp, Interface controlled electronic charge inhomogeneities in correlated heterostructures    
                                                                                                                                      PRL 97, 187001 (2006)  (cond-mat/0603629)
                         N.Pavlenko and T.Kopp, Electrostatic interface tuning in correlated superconducting heterostructures
                                                                                                                                      PRB 72, 174516 (2005) (cond-mat/0505714)
            Other papers on this subject:
                         N.Pavlenko and F.Schwabl, Superconductivity controlled by polarization in field-effect devices of confined geometry
                                                                                                                      Appl. Phys. Lett. 86, 012507 (2005) (cond-mat/0407696)
                         N.Pavlenko, Modulation of superconducting properties by ferroelectric polarization in confined FE-S-FE films
                                                                                                                      PRB 70, 094519 (2004) (cond-mat/0311376)
This project is focused on one of the central questions of heterogeneous catalysis: how the inhomogeneous
atomic arrangement of substrate layers affect the adsorption and chemical reactions on surfaces.

Here are the latest results on the CO adsorption and catalytic CO oxidation on the reconstructing Pt(100):
N. Pavlenko,  CO-activator model for reconstructing Pt(100) surfaces: local microstructures and chemical turbulence
                                                                                                                                           Phys. Rev. E. 77, 026203 (2008) (arXiv:0708.2840)
  Other relevant publications of this subject:
                             N. Pavlenko, R. Imbihl, J.W. Evans, and Da-Jiang Liu. Critical Behavior in an Atomistic Model for a Bistable Surface
                                                                Reaction: CO Oxidation   with Rapid CO Diffusion.  Phys. Rev. E 68, 016212 (2003).
                             N. Pavlenko, J.W. Evans, Da-Jiang Liu, and R. Imbihl. Catalytic CO oxidation on nanoscale Pt facets: effect
                                                 of inter-facet CO diffusion on bifurcation and fluctuation behavior. Phys. Rev. E 65, 016121 (2002).
                             N. Pavlenko, P.P. Kostrobij, Yu. Suchorski and R. Imbihl. Alkali metal effect on catalytic CO oxidation on a transition
                                                                                                                       metal  surface: a lattice-gas model. Surf. Sci. 489, 29 (2001)
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