C. V. Tomy

Observation of tunable exchange bias in Sr2YbRuO6

The double perovskite compound, Sr2YbRuO6, displays reversal in the orientation of magnetic moments along with negative magnetization due to an underlying magnetic compensation phenomenon. The exchange bias (EB) field below the compensation temperature could be the usual negative or the positive depending on the initial cooling field. This EB attribute has the potential of getting tuned in a preselected manner, as the positive EB field is seen to crossover from positive to negative value above Tcomp.

Multiferroic properties and magnetic structure of Sm1−xYxMnO3

We have successfully induced multiferroic behavior in the A-type antiferromagnet SmMnO(3) by the substitution of Y at the Sm site. A magnetic transition develops at similar to 24 K for Sm(1-x)Y(x)MnO(3) (x = 0.4, 0.5) which is not present in the parent compound. This transition coincides with the onset of electric order, with an electric polarization measured along the c axis. It is proposed that the effect of Y doping is to bring about a subtle distortion of the MnO(6) octahedra, causing a magnetic ordering of the Mn(3+) moments similar to that reported for the well-studied multiferroic TbMnO(3). Following on from our previous study on polycrystalline samples, we present measurements of the magnetic and electric properties of single-crystal Sm(0.6)Y(0.4)MnO(3) and Sm(0.5)Y(0.5)MnO(3). The data are summarized in a phase diagram for each of the principal crystallographic axes for the x = 0.5 compound. Powder neutron diffraction experiments on SmMnO(3) and Sm(0.6)Y(0.4)MnO(3) show that the Y substitution causes a change in the Mn-O-Mn bond angle toward the value found for TbMnO(3). The magnetic structure of Sm(0.6)Y(0.4)MnO(3) has been shown to consist of two phases: a sinusoidal ordering of the Mn(3+) moments below 50 K and a cycloidal ordering below 27 K. The cycloidal ordering occurs at the same temperature as the previously observed ferroelectric polarization, suggesting a similar multiferroic mechanism to that found in TbMnO(3).

Magnetization hysteresis and time decay measurements in FeSe0.50Te0.50: Evidence for fluctuation in mean free path induced pinning

We present results of magnetic measurements relating to vortex phase diagram in a single crystal of FeSe

Sign reversal of anisotropic magnetoresistance in La0.7Ca0.3MnO3/SrTiO3 ultrathin films

_{0.5}

Growth, characterization, vortex pinning, and vortex flow properties of single crystals of the iron chalcogenide superconductor FeCr0.02Se

Te

Structural, electronic, and magnetic properties of Sr2-xBaxFeMoO6(0≤x ≤2)

_{0.5}

Spintronic oscillator based on magnetic field feedback

which displays second magnetization peak anomaly for

Exchange bias-like magnetic properties in Sr2LuRuO6

H \parallel c

Coherent microwave generation by spintronic feedback oscillator.

. The possible role of the crystalline anisotropy on vortex pinning is explored via magnetic torque magnetometry. We present evidence in favor of pinning related to spatial variations of the charge carrier mean free path leading to small bundle vortex pinning by randomly distributed (weak) pinning centers for both

Dual role of an ac driving force and the underlying two distinct order–disorder transitions in the vortex phase diagram of Ca3Ir4Sn13

H \parallel c