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Публікація Thickness-dependent quantum oscillations of the transport properties in bismuth selenide thin films(Elsevier, 2019) Rogacheva, E. I.; Menshikova, S. I.; Sipatov, A. Yu.; Nashchekina, O. N.The objects of the present study were thin n-Bi2Se3 films with thicknesses d = 10–100 nm, grown by thermal evaporation of n-Bi2Se3 crystals in vacuum onto heated glass substrates. The room temperature d-dependences of the Seebeck coefficient, the Hall coefficient, and the electrical conductivity of the films exhibited an oscillatory behavior, which we attribute to quantum size effects. Such interpretation of the results is supported by the fact that experimentally determined values of the oscillation period are in quite good agreement with the theoretically calculated ones. We suggest that the large amplitude and undamped character of the oscillations in the studied range of thicknesses are connected with the topologically protected gapless surface states of Bi2Se3. The observed oscillatory character of the d-dependences of the transport coefficients should be taken into account when 2D-structures are applied in nanothermoelectricity and other fields of nanoscience and nanotechnology.Документ Dependences of thermoelectric properties on the thickness of thin films of indium doped lead telluride(Institute of Thermoelectricity, 2014) Menshikova, S. I.; Rogacheva, E. I.; Sipatov, A. Yu.; Matychenko, P. V.; Dobrotvorskaya, M. V.Dependences of thermoelectric properties (the Seebeck coefficient S, the electric conductivity σ, the Hall coefficient RH, the carrier mobilityμ and the thermoelectric power P = S²·σ) on the thickness d (d = 10 – 255 nm) of thin films prepared by vacuum evaporation of indiumdoped PbTe crystals and subsequent condensation on (111) BaF₂ substrates were obtained. With decreasing thickness of films to d ≈ 40 nm, there is n- to p-type inversion of conduction which is related to a change in thermodynamic equilibrium conditions and partial reevaporation of lead and/or indium atoms. Extremes were found on the thickness dependences of properties at d₁ ≈ 20 nm which is indicative of hole gas quantization. In the range of thicknesses with n-type conduction there is a smooth change in thermoelectric properties with thickness which testifies to manifestation of classical size effect and is sufficiently well described in the framework of the Fuchs-Sondheimer theory.Документ Size effects in thin n-PbTe films(STC "Institute for Single Crystals", 2015) Menshikova, S. I.; Rogacheva, E. I.; Sipatov, A. Yu.; Zubarev, Evgeniy N.Документ Size effects in chlorine doped PbSe thin films(Institute of Thermoelectricity, 2015) Menshikova, S. I.; Rogacheva, E. I.; Sipatov, A. Yu.; Krivonogov, S. I.; Matychenko, P. V.The possibility of obtaining strongly degenerate (≈ 3·10²⁰ сm⁻³) PbSe thin films (d = 5 – 220 nm) with n-type conductivity by thermal evaporation in vacuum of PbSe crystals doped with PbCl₂, with subsequent condensation onto (001) KCl substrates was established. It was shown that the films had high homogeneity degree, no grain structure was observed. The thickness dependences of thermoelectric properties (the Seebeck coefficient S, the Hall coefficient RH and the electric conductivity σ) of thin films were obtained. In the thickness range d ≈ 5 ÷ 30 nm, oscillation properties were observed with growth of d that are attributable to electron gas quantization. The calculation of S(d) dependence on the assumption of size quantization with regard to contribution of several subbands and the thickness dependence of the Fermi energy was shown to be in agreement with the experimental data. In the region of d > 30 nm there was growth of S and σ with thickness, which is attributable to manifestation of classical size effect and interpreted in the framework of Fuchs-Sondheimer and Mayer theories.