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The scaling behavior of the effective activation energy of high-quality epitaxial c-oriented Bi₂Sr₂Ca(Cu_1-xCo_x)₂O_d thin films with 0≤x ≤0.025 has been studied as a function of temperature and magnetic field. For all samples, the effective activation energy scales as U(T, μ_oH)=Uo(1-T/T_c)^mHⁿ with exponent m=1.25±0.03, n=-1/2 and the field scaling 1/μ_oH and -Uμ_oH for thick films and ultra thin films, respectively. The results are discussed taking into account of the influence of the Co substitution with a model in which U(T, H) arises from plastic deformations of the viscous flux liquid above the vortex-glass transition temperature.

MgB₂ thin films were deposited at low temperature substrates, in situ, on c-plane sapphire substrates, with the aluminium nitride (AlN) buffer layers, using the multiple-target sputtering system. The magnetoresistivities were measured using dc-five probe method in applied magnetic field up to 9 Tesla. The upper critical field anisotropy, H_C2(T) and irreversibility field H_irr(T) versus temperature were determined. The Hall coefficients R_H are slightly temperature dependent and positive in the normal state. The critical temperature of 30–32 K and critical current density of 10⁶-10⁷A/cm² at 4.2 K were obtained. Using extracted data, the coherence length ξ_o, anisotropic coefficient γ and penetration depth λ_L were calculated.

This paper presents the results of a study of the growth and structure properties of Pb${}_{1-x}$Eu_xTe, ($x=0.05$) epitaxial films with 0.5–1$\mu$m thickness, grown on BaF₂ and SiO₂ substrates oriented in the (111) direction, by the molecular beam condensation method in a vacuum of 10${}^{-4}$ Pa with the use of an additional compensating source of Te vapor during the growth process. The optimal conditions for obtaining structurally perfect ($W_{1/2}=90$–100${}^{\prime \prime }$) epitaxial films were established: $T_{\mathrm{\text{sub}}}=573$–623K; $T_{\mathrm{\text{Te}}}=410$K; ${\upsilon }_c=8$–9 Å/s. It was determined that conductivity inversion occurs at the temperature of the compensating source 410K.