Laboratory of Nonequilibrium Processes in Semiconductors

Nina Agrinskaya

Ph.D, Sci.D.,
Leading Researcher

Current Research Focus
Recent Publications
Books and Reviews
Research Retrospective
Contact Information

Current Research Focus

  • Metal-insulator transition in 2D structures and 2D hopping conductivity
    To explain the main features of the metal-insulator transition (MIT) in 2D we suggest a simple model taking into account strongly localized states in the band tail of 2D conductivity band with a specific emphasize of a role of doubly-occupied states (upper Hubbard band (UHB)). By selective doping of the well and barrier regions the situation was realized where the upper Hubbard band (A+ , D- centers) was occupied at the equilibrium and the conductivity was over the corresponding states. The experiments for GaAs/AlGaAs multiple quantum well structures showed that the binding energy of A+ centers increases significantly for well widths 15 nm with respect to the bulk case which is related to comparability between the well width and radius of A+ state. The corresponding 2D hopping conductivity and magnetoconductance over the states of the UHB are considered for the different well widths and different impurities.
  • Optical spectroscopy and nonlinear optics of organic materials
    Most intensive research concerning optical spectroscopy and nonlinear optics is now concentrated on structures with lowered dimensionality, particularly a specific interest is paid to 1D and 0D organic compounds. Optical absorption, luminescence and nonlinear optical susceptibilities are investigated in our group for different molecular compounds including polymers and polycrystalline molecular materials.

Recent Publications (2003-2007)
  1. Н.В.Агринская, В.И.Козуб, Д.С.Полоскин.
    Виртуальный переход Андерсона в узкой примесной зоне легированных слоев p-GaAs/AlGaAs.
    Письма в ЖЭТФ, vol. 85, issue 3, page 202-207, 2007
  2. N.V. Agrinskaya, V.I. Kozub, D.V. Poloskin, A.V. Chernyaev, and D.V. Shamshur.
    Crossover from Strong to Weak Localization in the Split-Off Impurity Band in Two Dimensional p-GaAs/AlGaAs Structures.
    Phys.stat.sol. (C), v.3, p.329, 2006
  3. N.V.Agrinskaya, V.I.Kozub, A. Chernyaev, D.V Shamshur.
    Magnetoresistance of p-GaAs/AlGaAs structuresin the vicinity of metal-insulator transition: Effect of superconducting leads.
    Phys.Rev.B, v.72, p.085337, 2005
  4. Агринская Н.В., Козуб В.И., Полоскин Д.В., Черняев А.В., Шамшур Д.В.
    Переход от сильной к слабой локализации в отщепленной примесной зоне в двумерных структурах p-GaAs-AlGaAs.
    Письма в журнал экспериментальной и теоретической физики , т.80, с.36-40, 2004
  5. Agrinskaya N.V., Kozub V.I., Chernyaev A.V., Shamshur D.V.
    Manifestation of Coulomb gap in two-dimensional p-GaAs/AlGaAs structures withfilled lower or upper Hubbard bands.
    Phys. Stat. Sol. (c) v.1, p.121-125, 2004
  6. Агринская Н.В., Иванов Ю.Л., Петров П.В., Устинов В.М.
    Photoluminescence and transport in selectively doped p-GaAs-AlGaAs quantum wells:manifestation of the upper hubbard band.
    Solid State Communications, т. 126, с.369-372, 2003

Books and Reviews
N.V.Agrinskaya, T.V.Mashovets. Self-compensation in semiconductors: a review dedicated to the hundredth anniversary of the birthday of Y.I.Frenkel. Semiconductors 28, 843-857, 1994

Research Retrospective
  • Variable range hopping conductivity [1-3]
  • Optical spectroscopy of Polydiacetylenes [4-5]
  • Highly conducting channels in polymer films [6]
  • Defects in AIIBVI compounds [7-8]

References (Most Important)

  1. Agrinskaya N.V. Low temperature variable range hopping conductivity in doped CdTe crystals. Journal of Crystal Growth, v.138, p.493-498, 1994.
  2. Agrinskaya N.V., Kozub V.I. Effect of preexponential factors on temperature behavior of VRH conductivity. Solid State Commun. V.91, p.853-857, 1994
  3. Agrinskaya N.V., Kozub V.I. Suppression of negative magnetoresistance in Coulomb Gap regime: quantun interference and spin effects in CdTe. Phys.Stat.Sol.(b) v.205, p.11-15, 1998
  4. Agrinskaya N.V., Guk E.G., Kudryavtsev I.A., Lublinskaya O.G. Linear and nonlinear optical spectroscopy of polydiacetilene THD in PMMA matrix. Nonlinear Optics v.12, p.301-307, 1995
  5. Agrinskaya N.V.,Guk E.G., Remizova L.A. Non-linear optical properties modification in some substituted polydiacetylenes due to change of basisity constant of the side groups. Synth. Metals, v.54, 289, 1993
  6. Agrinskaya N.V., Kozub V.I. On the mechanism of formation of highly conducting channals in polymer films. Solid state comm. v.106, p.111-114, 1998
  7. Agrinskaya N.V., Arkadeva E.N. Matveev O.A. Donor-cadmium vacancy association in CdTe. Procedings of Int.Symp. on CdTe, Strasbourg, France, 1971, p.9
  8. Agrinskaya N.V., Arkadeva E.N. Fermi level pinning in the middle of the band gap in the CdTe:Cl crystals: role of deep localized states. Phys. Stat. Solidi (b), v.143, K103, 1987

Contact Information

 Tel.: +7 (812) 292 7358
E-mail: nina.agrins@pop.ioffe.rssi.ru

Nina Agrinskaya
Laboratory of Nonequilibrium Processes in Semiconductors
Ioffe Physico-Technical Institute, Russian Academy of Sciences
Politekhnicheskaya 26,
St.Petersburg, 194021 Russia

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