Natalia Nikolaevna KOVALEVA - Max Planck Institute for Solid State ...

CURRICULUM VITAE
Natalia N. KOVALEVA, Ph. D. (Solid State Physics)
Present address:
Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, Stuttgart, D-70569 GERMANY
Tel.: +49-(0)711-6891731 e-mail: N.Kovaleva@fkf.mpg.de
FAX: +49-(0)711-689-1632 / for N. Kovaleva
http://www.mpi-stuttgart.mpg.de/en/fr_physics.html
1. Personalia
Name
Natalia Nikolaevna KOVALEVA
Place of birth
Beltsi, Moldavian SSR, USSR
Citizenship
Russian Federation
2. Education
Ph.D. June 1989
(Solid State Physics)
Institute of Solid State Physics (ISSP), Russian Academy of Sciences (RAS),
Chernogolovka, Moscow distr., RUSSIA http://www.issp.ac.ru
M. Sc. June 1983
(Physics and Engineering)
3.Employment
Diploma with Honor Moscow Institute of Physics and Technology (MIPT),
Department of General and Applied Physics, Moscow, RUSSIA http://www.mipt.ru
1/2006 – present
1/2008 – 1/2009
10/2001 – 12/2005
Research Scientist, Physics Department, Max-Planck Institute for Solid State
Physics, Stuttgart, D-70569 GERMANY
Lecturer in Physics, Physics Department, Loughborough University, Leicestershire,
LE11 3TU UK
Research Scientist / Max-Planck Society Fellowship, Physics Department, Max-
Planck Institute for Solid State Physics, Stuttgart, D-70569 GERMANY
01/2000 – 09/2001
Research Scientist, Institute of Solid State Physics, Russian Academy of Sciences,
Chernogolovka, Moscow distr., 142432 RUSSIA
01/1999 – 12/1999
Postdoctoral Fellowship Program, Royal Society/NATO, Department of Physics
and Astronomy, CMMP, University College London, Gower Street, London WC1
6BT, UK
01/1992 – 12/1998
01/1989 – 04/1990
10/1983 – 12/1988
Research Scientist, Institute of Solid State Physics, Russian Academy of Sciences,
Chernogolovka, Moscow distr., 142432 RUSSIA
Junior Researcher and Post-Graduate, Institute of Solid State Physics, Russian
Academy of Sciences, Chernogolovka, Moscow distr., 142432 RUSSIA
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4. Current research activity
2001– present. Max-Planck Institute for Solid State Physics, Stuttgart – in collaboration with Prof. C. Bernhard and
Prof. B. Keimer.
Optical spectral weight (SW) redistribution caused by magnetic interactions in Mott-Hubbard insulators, such as
LaMnO 3 , YTiO 3 , and LaTiO 3 ; Charge dynamics in iron-based superconductor LaFeAsO 1-x F x ; C-axis and in-plane optical
conductivity of YBa 2 Cu 3 O 6..9 in a wide spectral range (FIR, mid-IR, UV-VIS); IR study of optical conductivity
in Na x CoO 2 ; C-axis lattice dynamics in single-, bi-, and trilayer Bi-cuprate HTSCs; Assignment of the IR and Raman-active
phonons in YTiO 3 , TiOCl and NaCoO 2 , calculation of the eigenvector components, dynamic effective
charges, and etc. [1-16].
Methods employed: Polarized angle-resolved optical probes in a wide spectral range (FIR, mid-IR, UV-VIS) and
temperature range (10-400 K) such as ellipsometry, reflectance and transmittance spectroscopy are used. Theoretical
group analysis and lattice dynamical calculations are applied in the interpretation of IR and Raman phonon spectra.
5. Scientific research experience and references
1999 – 2000. University College London, Department of Physics and Astronomy, CMMP – in collaboration with
Phof. A.M. Stoneham.
Modeling of polaron-related features in systems of complex oxides exhibiting “colossal magnetoresistance” (CMR)
effect in the framework of shell model approximation and Mott-Littleton approach [17-19].
Methods employed: Determination of shell model parameters from lattice equilibrium conditions and consistency
with experimental optical phonon frequencies and high- and zero- frequency dielectric constants. Defect calculations
in the Mott-Littleton approach using the shell model parameters. Calculation of key electronic and ionic polarization
energies associated with localized electronic charge carriers. Calculation of optical charge-transfer transitions in a
Born-Hyber cycle.
1996 – 1998. ISSP RAS – in collaboration with Dr. A.V. Bazhenov ISSP RAS; Dr. P.J.M. van Bentum, High-field
Magnet Laboratory, University of Nijmegen, The Netherlands; Prof. S-W. Cheong, Rutgers Univeristy, Piscataway,
New Jersey, USA; Prof. N.-C. Yeh, California Institute of Technology, Pasadena, USA.
Expeperimental IR-study of optical conductivity in correlated 3d-electron systems of doped perovskite manganites of
Re 1-x A x MnO3. IR reflectivity of La 0.7 Ca 0.3 MnO 3 single crystal was investigated over a broad range of temperatures
(78-340 K), magnetic fields (0-16 T), and frequencies (20-10000 cm –1 ). A strong reduction of the effective dc resistivity
extrapolated from IR optical conductivity is found with increasing external magnetic field in the vicinity of the
Curie point – the first observation of the “optical CMR” effect at IR frequencies. The temperature and magnetic field
dependencies of the optical conductivity are characterized by the interplay between the Drude-like and polaron features,
indicating the importance of electron-phonon coupling and double exchange mechanism in the description of
the CMR effect [22-25].
Methods employed: IR reflectance and transmittance spectroscopy in a broad range of temperatures (10-340 K),
magnetic fields (0-16 T), and frequencies (20-10000 cm –1 ).
1983 – 1996. ISSP RAS, Ph. D. (1989) – in collaboration with Prof. S.I. Bredikhin and Prof. Yu.A. Ossipyan;
Studies of electronic subsystem and mechanism of interaction between electronic and ionic subsystems in superionic
conductors. Investigations of optical properties and ac-conductivity of RbAg 4 I 5 superionic conductor, associated with
intrinsic crystal defects. Investigation of relaxation and steady-state processes at the electronic conductor-superionic
conductor boundary. The mechanisms of the low-temperature photoluminescence and color center formation due to
additive coloring and ionic implantation were studied. The exposure-induced absorption under light irradiation into
the impurity excitation region was discovered and investigated. The new phenomena observed are associated with
specific features of electronic excitation process due to the presence of the mobile ionic subsystem [26-39].
Methods employed: Low-temperature photoluminescence, UV-VIS optical absorption, space-resolved optical spectroscopy,
dc/ac ionic and electronic conductivity measurements.
1981 – 1983. MIPT & ISSP RAS, M. Sc. (1983) – in collaboration with Dr. Sc. K.P. Meletov and Prof. E.F. Sheka;
Studies of deep impurity centers in molecular crystals (naphthalene) by optical methods. Investigations of the anomalies
of phonon spectra of impurity centers by using temperature modulation technique of low-temperature luminescence
spectra [40].
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6. Presentations at conferences and seminars
- Orbital Workshop 2009, 7-8 October 2009, Helmholtz-Zentrum Berlin, Germany.
- Conference on Magnetism ICM’2009, 26-31 July 2009, Karlsruhe, Germany.
- Spin Transport in Condensed Matter, The 23 rd Nishinomiya-Yukawa Memorial International Workshop, 23 October
– 28 November, 2008, Kyoto University, Kyoto, Japan.
- Orbital’2007, 6 th Workshop on Orbital Physics and Novel Phenomena in Transition Metal Oxides, 10-11 October
2007, Stuttgart, Germany.
- 2 nd International Conference on Fundamental Problems of High Temperature Superconductivity (FPS’06), 9-13
October 2006, Moscow, Russia.
- Conference on Magnetism ICM’2006, 20-25 August 2006, Kyoto, Japan.
- Strongly Correlated Electron Systems SCES’05, 26-30 July 2005, Vienna, Austria
- Electronic Correlations and Magnetism (EKM) group seminar, University of Augsburg, 2 December 2004,
Augsburg, Germany (invited by Prof. A. Loidl).
- Physics Department Seminar, Loughborough University, 16 December 2004, Loughborough, UK (invited by
Prof. Kusmartsev).
- Spectroscopies in Novel Superconductors SNS’2004, 11-16 July, Sitges, Spain.
- Strongly Correlated Electron Systems SCES’04, 26-30 July 2004, Karlsruhe, Germany.
- International Workshop MSU-HTSC VII, 20-25 June 2004, Moscow, Russia.
- Orbital Physics and Novel Phenomena in Transition Metal Oxides, 3 rd Berlin Workshop on Orbital Physics, 6-7
October 2004, Berlin, Germany.
7. Collaborations during 2001 – 2010.
1) Max Planck Institute for Solid State Research, Stuttgart, Germany.
2) Physics Department, Loughborough University, United Kingdom.
4) Department of Physics, University of Fribourg, Switzerland.
5) Experimentalphysik V, University of Augsburg, Germany.
6) Institute for Synchrotron Radiation, Forschungszentrum Karlsruhe, Karlsruhe, Germany.
7) Institute of Condensed Matter Physics, Masaryk University, Brno, Czech Republic.
8) University College London, London WC1E 6BT, United Kingdom.
8. Teaching experience
1. Lectures at Physics Department, Loughborough University - “Introduction to Holography” - facultative course in the
course of “Modern Optics”.
Content: Physical principles of holography. Image formation and registering. Optical ways, equipment and procedures.
Interaction of radiation with matter. Main equations in holography. Linear systems in optics. Fourier transforms. Convolutions.
Theory of diffraction. Frauenhoffer diffraction. Geometry of holographical images. Applications of holography.
2. Supervising postdoc and master students during 2001 – 2010.
9. Total number of publications: more than 40, with total number of citations 415.
During 2001-2010: 1 Science report, 4 Phys. Rev. Lett., 9 Phys. Rev. B.
10. List of publications
1. N. N. Kovaleva, A. V. Boris, L. Capogna, J. L. Gavartin, P. Popovich, P. Yordanov, A. Maljuk, A. M. Stoneham, and B. Keimer – “Dipole-active optical phonons in
YTiO 3 : Ellipsometry study and lattice-dynamics calculations”, Phys. Rev. B 79, 045114 (2009).
2. D. Menzel, P. Popovich, N. N. Kovaleva, J. Schoenes, K. Doll, A. V. Boris – “Electron-phonon interaction and spectral weight transfer in Fe 1-xCo xSi”, Phys. Rev. B 79,
165111 (2009).
3. W. Knafo, C. Meingast, A. V. Boris, P. Popovich, N. N. Kovaleva, P. Yordanov, A. Maljuk, R. K. Kremer, H. v. Loehneysen and B. Keimer – “Ferromagnetism and
lattice distortions in the perovskite YTiO 3”, Phys. Rev. B 79, 054431 (2009).
4. A. V. Boris, N. N. Kovaleva, S. S. A. Seo, J. S. Kim, P. Popovich, Y. Matiks, R. K. Kremer, and B. Keimer – “Signatures of electronic correlations in optical properties
of LaFeAsO 1-xF x“, Phys. Rev. Lett. 102, 027001 (2009).
5. N. N. Kovaleva, A. V. Boris, P. Yordanov, A. Maljuk, E. Bucher, J. Strempfer, M. Konuma, I. Zegkinoglou, C. Bernhard, A. M. Stoneham, and B. Keimer – “Optical
response of ferromagnetic YTiO 3 studied by spectral ellipsometry”, Phys. Rev. B 76, 155125 (2007).
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6. N. N. Kovaleva, A. V. Boris, C. Bernhard, A. Kulakov, A. Pimenov, A. M. Balbashov, G. Khaliullin, and B. Keimer – “Spin-Controlled Mott-Hubbard Bands in
LaMnO 3 Probed by Optical Ellipsometry”, Phys. Rev. Lett. 93, 147204 (2004).
7. A. V. Boris, N. N. Kovaleva, O. V. Dolgov, T. Holden, C.T. Lin, B. Keimer, and C. Bernhard - “In-plane spectral weight shift of charge carriers in YBa 2Cu 3O 6.9”,
Science 304, 708 (2004).
8. C. Bernhard, A. V. Boris, N. N. Kovaleva, G. Khaliullin, A. Pimenov, L. Yu, D. P. Chen, C.T. Lin, and B. Keimer – “Charge ordering and magneto-polarons in
Na 0.82CoO 2”, Phys. Rev. Lett. 93, 167003 (2004).
9. G. Caimi, L. Degiorgi, N. N. Kovaleva, P. Lemmens, and F. C. Chou - “Infrared optical properties of the spin-1/2 quantum magnet TiOCl”, Phys. Rev. B 69, 125108
(2004).
10. N. N. Kovaleva, A. V. Boris, D. Munzar, T. Holden, C. Ulrich, B. Liang, C.T. Lin, J. L. Tallon, A. M. Stoneham, B. Keimer, and C. Bernhard – “C-axis lattice dynamics
in Bi-based cuprate superconductors”, Phys. Rev. B 69, 054511 (2004).
11. P. Lemmens, V. Gnezdilov, N.N. Kovaleva, K.Y. Choi, H. Sakurai, E. Takayama-Muromachi, K. Takada, T. Sasaki, F.C. Chou, D. P. Chen, C.T. Lin and B. Keimer –
“Effect of Na content and hydration on the excitation spectrum of the cobaltite Na xCoO 2 yH 2O”, J. Phys.: Condens. Matter 16, S857 (2004).
12. C. Bernhard, T. Holden, A. V. Boris, N. N. Kovaleva, A. Pimenov, J. Humlicek, C.T. Lin, J.L. Tallon - “Anomalous oxygen isotope effect on the in-plane far-infrared
conductivity of detwinned YBa 2Cu 3 16,18 O 6.9 ”, Phys. Rev. B 69, 052502 (2004).
13. P. Lemmens, K.Y. Choi, G. Caimi, L. Degiorgi, , N. N. Kovaleva, A. Seidel, F.C. Chou - “Giant phonon softening in the pseudo-gap phase of the quantum spin system
TiOCl”, Phys. Rev. B 70, 134429 (2004).
14. A. V. Boris, D. Munzar, N. N. Kovaleva, B. Liang, C.T. Lin, A. Dubroka, A.V. Pimenov, T. Holden, B. Keimer, Y.-L. Mathis, and C. Bernhard – “Josephson plasma
resonance and phonon anomalies in trilayer Bi 2Sr 2Ca 2Cu 3O 10”, Phys. Rev. Lett. 89, 277001 (2002).
15. N. N. Kovaleva, J.L. Gavartin, A.L. Shluger, A. V. Boris, and A.M. Stoneham – “Lattice relaxation and charge-transfer optical transitions due to self-trapped holes in
nonstoichiometric LaMnO 3 crystal”, JETP 94, 178 (2002).
16. N. N. Kovaleva, J.L. Gavartin, A.L. Shluger, A. V. Boris, and A.M. Stoneham – “Formation and relaxation energies of electronic holes in LaMnO 3 crystal”, Physica B
312–313, 734 (2002).
17. N. N. Kovaleva, J.L. Gavartin, A. V. Boris, and A.M. Stoneham – “Optical transitions in non-stoichiometric LaMnO 3 Identifying the charge-transfer transitions”,
Physica B 312–313, 737 (2002).
18. A. V. Boris, C. Bernhard, N. N. Kovaleva, P. Mandal, and A. Loidl – “Phonon anomalies in the infrared conductivity of the RuSr 2GdCu 2O 8 ferromagnetic superconductor”,
Physica B 312–313, 797 (2002).
19. A. V. Boris, P. Mandal, C. Bernhard, N. N. Kovaleva, K. Pucher, J. Hemberger, and A. Loidl – “Phonon anomalies and electron-phonon interaction in the
RuSr 2GdCu 2O 8 ferromagnetic superconductor: Evidence from infrared conductivity”, Phys. Rev. B 63, 184505 (2001).
20. A. V. Boris, N. N. Kovaleva, A.V. Bazhenov, P.J.M. van Bentum, Th. Rasing, S- W. Cheong, A.V. Samoilov, N.-C. Yeh, - "Infrared studies of a La 0.7Ca 0.3MnO 3 single
crystal: optical magnetoconductivity in a half-metallic ferromagnet", Phys. Rev. B 59, R697-R700 (1999).
21. A. V. Boris, N. N. Kovaleva, A.V. Bazhenov, A.V. Samoilov, N.-C. Yeh, R.P. Vasquez, - "Infrared optical properties of La 0.7Ca 0.3MnO 3 epitaxial films", J. Appl. Phys.
81, 5756 (1997).
22. A.V. Bazhenov, A. V. Boris, N. N. Kovaleva, A.V. Samoilov, N.-C. Yeh, R.P. Vasquez, - "Spectra of dipole-active optical phonons in La 0.7Ca 0.3MnO 3 epitaxial films",
Inst. Phys. Conf. Ser. 160, 429 (1997).
23. N. N. Kovaleva, A. V. Boris and T. Awano,-"Color center formation and electronic excitation processes in superionic crystals RbAg 4I 5", Solid State Ionics 93, 303
(1997).
24. N. N. Kovaleva, A. Ionov, - “X-ray irradiation influence on photoluminescence of γ - RbAg 4I 5 superionic crystals”, Solid State Ionics 86-88, 267 (1996).
25. N. N. Kovaleva, A. V. Boris, S.Bredikhin, T.Awano - "Photoinduced color centers creation in superionic crystals RbAg 4I 5", Radiation Effects and Defects in Solids
134, 457 (1995).
26. S.Bredikhin, N. N. Kovaleva,T. Hattori, and M. Ishigame - "Photoinduced phenomena in RbAg 4I 5 superionic crystals", Solid State Ionics 74, 457 (1994).
27. S.Bredikhin, N. N. Kovaleva, N. V. Lichkova - "The effect of point defects on the ionic conductivity of RbAg 4I 5 solid electrolytes”, Radiation Effects and Defects in
Solids 119-121, 729 (1991).
28. N. N. Kovaleva, A. V. Boris, S.I.Bredikhin, N. V. Lichkova – “Investigation of near-electrode regions in superionic RbAg 4I 5 crystals”, Solid State Ionics 40, 266
(1990).
29. N. N. Kovaleva, S.I.Bredikhin, N. V. Lichkova – “The effect of point defects on the ionic conductivity of RbAg 4I 5 solid electrolytes”, Solid State Ionics 40, 180 (1990).
30. S.Bredikhin, N. V. Zagorodnev, N. N. Kovaleva, N. V. Lichkova – “Photoluminescence of solid electrolyte RbCu 4Cl 3I 2”, Solid State Ionics 37, 83 (1989).
31. N. N. Kovaleva, S. I. Bredikhin, A. V. Boris, N. V. Lichkova – “Investigation of the near-electrode regions in the electrochemical cell Ag/RbAg 4I 5/C by optical methods”,
Fiz. Tverd. Tela 31, 47 (1989).
32. N. N. Kovaleva, S. I. Bredikhin, N. V. Lichkova – “Effect of additive coloring on the ionic conductivity of solid electrolyte RbAg 4I 5”, Zh. Exp. Teor. Phys. 96, 735
(1989).
33. S. I. Bredikhin, N. N. Kovaleva, I. Sh. Khasanov, N. V. Lichkova – “Effect of ion implantation on the luminescence and light absorption in superionic crystals
RbAg 4I 5”, Fiz. Tverd. Tela 30, 1901 (1988).
34. S. I. Bredikhin, N. N. Kovaleva, N. V. Lichkova – “Electron emission in RbAg 4I 5 crystals stimulated by phase transitions”, Solid State Ionics 28-30, 200 (1988).
35. S. I. Bredikhin, N. N. Kovaleva, N. V. Lichkova, A. V. Poletaev, S. Z. Shmurak – “Electron emission stimulated by phase transitions in superionic RbAg 4I 5 crystals”,
Fiz. Tverd. Tela 29, 772 (1987).
36. S. I. Bredikhin, N. N. Kovaleva, N. V. Lichkova – “On the mechanism of the luminescence in the superionic crystals RbAg 4I 5”, Fiz. Tverd. Tela 28, 2813 (1986).
37. N. N. Kovaleva, K. P. Meletov, E. F. Sheka – “Anomalies of phonon wings of impurity centers”, Zh. Exp. Teor. Phys. 60, 1204 (1984).
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