<Emphasis Type="Italic">N</Emphasis>-shaped voltage-current characteristic and current oscillations in Sm<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript> Sr<Subscript>x</Subscript>MnO<Subscript>3</Subscript> manganite

The voltage-current characteristics (VCC) of Sm_1?xSr_x MnO₃ samples with x=0.425 and x=0.450 were experimentally studied at a temperature of 77 K in pulsed and constant electric (E) and magnetic (H) fields up to 10 kOe for the H‖E and H⊥E orientations. N-shaped VCCs and high-frequency (up to 3 MHz) current oscillations were observed. It was found that the effect of colossal magnetoresistance had a threshold character and was smoothly reduced to zero with E→0.     

Temperature–Frequency Dependence of the Dielectric Response in LuFe2O4 Multiferroics

Physics of the Solid State - The temperature–frequency spectra of the complex dielectric permittivity of the LuFe2O4 multiferroics have been studied in the temperature range 100–400 K...     

The Feigenbaum—Sharkovskii—Magnitskii scenario of transition to chaos in a circuit with a tunnel diode

The scenarios of transition to a chaotic state in a circuit with a tunnel diode are experimentally studied. It is shown that there are regions on the plane of control parameters where the Feigenbaum scenario and the Sharkovskii order alternate and chaos is reached through intermittency.     

Recombination instability and domainisation inp-Ge(Au)

Results of an experimental study of short and longp-Ge(Au) samples are presented and compared qualitatively with data furnished by the one-dimensional theoretical model describing the evolution of domain instability in a two-parametric space ‘voltageV-emission coefficient β’. According to the theory, single-, double-, and multi-subdomain states and order-disorder-order transitions via intermittency have been observed in the system with increasing voltage. Three operation regimes of the system are found, depending on the region of the parametric space: ohmic, quenched (pulsing) and transit-time. In short samples, a second portion with S-switching is revealed in the current-voltage characteristic.     

Effect of Frequency of the Alternating Electric Field on Temperature Impedance Spectra of LuFe<Subscript>2</Subscript>O<Subscript>4</Subscript> Ceramic Multiferroic

Temperature impedance spectra are measured on LuFe₂O₄ ceramic multiferroics over a temperature range of 100–400 K, upon applying a sinusoidal voltage with a frequency varying between 20 Hz and 120MHz. At signal frequencies of 30–70 MHz, spectra exhibit features such as an abnormal positive temperature resistance coefficient within the temperature range of 200–260 K, which are interpreted in the context of the generalized barrier model.     

Conductivity of semiconductor diodes with simultaneously applied direct and alternating biases

The influence of a high-amplitude high-frequency signal on the static current-voltage characteristics of commercial semiconductor p-n junction diodes is studied experimentally. S-shaped regions are observed in the direct branches of the current-voltage characteristics over a wide frequency range, and a bell-shaped segment is seen in the reverse branches. The value and position of the latter on the voltage axis considerably depend on the alternating signal frequency.