Articles you may be interested inA uniform model for direct and converse magnetoelectric effect in laminated composite Appl. Phys. Lett.

The inverse magnetoelectric MEE-effect in the SmFe3(BO3)4 single-crystal sample in an applied electric field has been studied. The electric field E consists of two components: a constant one, e0, and a variable one, e × cos(ωt). The investigated compound evokes great interest due to the existence of both linear and quadratic contributions to the magnetoelectric effect. According to theoretical analysis, the effective susceptibility of the first harmonic of magnetic moment oscillations depends on the dc electric field component e0. Indeed, according to the measurement data, the dc field e0 significantly affects the MEE-effect first-harmonic amplitude: depending on the e0 sign, these oscillations can be either amplified or suppressed. This offers an opportunity for controlling the magnetic moment oscillation amplitude at the applied electric field frequency, including the signal modulation, which is promising for application. In the applied dc field e0, a slight change in the susceptibility of the MEE-effect term quadratic to the electric field was detected. The mathematical apparatus used correctly describes the qualitative dependence of the MEE-effect amplitude on the dc field e0, while the quantity appears to be approximately twofold overestimated.

Orthorhombic Pb2Fe2Ge2O9 antiferromagnetic single crystals have been synthesized by a modified pseudo-flux technique and their magnetic, thermodynamic, and magnetodielectric properties have been investigated. It has been found that, below the Neel temperature (45.2 K), iron moments are arranged in a canted antiferromagnetic structure with a weak ferromagnetic moment parallel to the a axis. According to the specific heat measurement data, the TN value remains invariable in applied magnetic fields of up to 5 T within the experimental accuracy. The magnetic entropy in the investigated crystals attains 2Rln(2S+1) right above TN, which is indicative of a purely magnetic nature of the transition. It has been shown that the weak ferromagnetic moment is induced by the interplay between the single-ion anisotropy and antisymmetric Dzyaloshinskii-Moriya exchange interaction, with the latter contribution being dominant. It has been established from the angular dependences of the magnetization in three orthorhombic planes that the symmetries of the magnetic and crystal structure are identical. The magnetodielectric properties of the Pb2Fe2Ge2O9 single crystals have been studied at different mutual orientations of the electric and magnetic fields. The most prominent anomalies have been observed in the vicinity of the spin-flop transition in a magnetic field applied along the c axis.

No abstract