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Remarkable applicability of magnetic Compton scattering (MCS) in deducing site specific small spin moments like those in LaFe1-xNixO3 (x = 0.4 and 0.5) is established. The MCS measurements revealed that Fe site gives a dominant contribution (although small) to total magnetic moment, while the contribution of Ni spin moment is found to be antiparallel to that of Fe moment. Present work, which instigates insignificant role of orbital moment and diffused components in the formation of total magnetic moment, triggers era of applications of MCS in ferrimagnetic compounds with small magnetic moments. [ABSTRACT FROM AUTHOR]

The 3d Mn orbitals in Pr0.25Ca0.25MnO3 (PCMO), in the ferromagnetic phase, were imaged by two-dimensional reconstruction of spin-polarized electron-momentum density projected along the [100] and [110] principal directions. The results were analyzed using a molecular-orbital scheme to understand the population distribution for the t2g and the eg states for Mn. The analysis shows that the t2g states are found to be half-filled, whereas, the eg states are dominated mainly by x2−z2-type orbitals for both projected [100] and [110] principal directions. The observance of preferential filling of the x2−z2-orbital type is consistent with a cooperative Jahn-Teller distortion of the MnO6 octahedra leading to a local tetragonal compression along the y axis for this system. As a result of this distortion, the 3y2−r2-type orbitals have a small population for PCMO; the ratio of the x2−z2-type orbitals to that of the 3y2−r2-type orbitals is greater than 2, similar to that seen for bilayered manganites. [ABSTRACT FROM AUTHOR]

The larva of Chilostigma sieboldi McLachlan is described. This is the first positive association of adults and larvae in the genus Chilostigma, which involves only two species in the boreal region. We recorded and confirmed the Holarctic species C. sieboldi from Kushiro Mire in eastern Hokkaido by close examination of male and female genitalia. In Japan this species has been collected only from Kushiro Mire. [ABSTRACT FROM AUTHOR]

Candidiasis of the esophagus progressing to stricture formation in a 74-year-old male is reported. Esophageal candidiasis develops in the presence of various predisposing conditions such as long-standing administration of antibiotics or corticosteroids, and malignancy. The first endoscopic examination of this patient revealed unusual multiple black plaques in the esophagus. Despite intensive exploration, no predisposing factors were found. The stricture was progressive, despite the administration of adequate antifungal therapy, and its presence necessitated several attempts at dilatation. Case reports of esophageal candidiasis without underlying disease are very rare. [ABSTRACT FROM AUTHOR]

The magnetic properties of the polycrystalline Heusler compound Co2TiAl were investigated by the classical experimental methods and the magnetic Compton scattering experiment. The X-ray diffraction profile at room temperature can be identified as the phase of the L21-type ordered structure. The magnetic field and temperature dependence of magnetization show that Co2TiAl has the typical soft ferromagnetic properties with TC of 120 K and the saturation magnetization of 0.70 \muB per formula unit. The resistivity shows a typical metallic behavior at temperatures up to 300 K. The magnetoresistance (MR) effect with the MR ratio of -8% appears in the vicinity of TC. The characteristics of the magnetic Compton profile are similar to that of the well-known ferromagnetic metals such as Ni and Fe. The experimental results indicate that the origin of the MR effect observed for Co2TiAl is similar to that for conventional ferromagnetic materials. [ABSTRACT FROM AUTHOR]

Spin and orbital magnetic moments in hole doped manganite La0.7Ca0.3Mn1-xAlxO3 (x = 0, 0.02, and 0.06) have been scrutinized using experimental spin momentum densities. An analysis of magnetic Compton profiles shows that the spin moment of Mn 3d has a major contribution towards the total spin moment and its contribution decreases as we increase the concentration of Al. The present experiment along with magnetization data predict orbital moment of -0.29 ± 0.03 μB/f.u. in the parent compound (x = 0), which almost disappears on substitution of Al. The results are explained on the basis of imbalance in Mn3+ and Mn4+ charge ratio in these compounds. [ABSTRACT FROM AUTHOR]

We have carried out magnetic Compton scattering measurements on polycrystalline samples of the perovskite manganites La1-xSrxMnO3 covering the hole-doping range from x=0.1 to x=0.5. Charge and magnetic Compton profiles were measured in order to obtain Compton profiles of spin-wise subbands. By considering the doping-dependency of the subband Compton profiles, we show how the electronic states evolve associated with hole doping. The results indicate that doped holes predominantly enter into the O 2p states in the lightly doped region and the charge transfer occurs from the up-spin Mn 3d to the down-spin Mn 3d states in the heavily doped region. [ABSTRACT FROM AUTHOR]

Temperature and field dependent magnetic Compton profiles of BixCo2-xMnO4 (x=0 and 0.3) multiferroics are reported. The magnetic Compton profiles and total spin moments are interpreted in terms of Mn/Co-3d contribution. Mn spin moments are found to be dominating in total magnetization whereas a small contribution of Co spin moment couples antiferromagnetically with that from Mn sites. The magnetic Compton data when compared with magnetization data, interestingly, show a reverse trend of orbital magnetic moments which are explained in terms of exchange interaction between the ions at different sites via O2- ions. [ABSTRACT FROM AUTHOR]

Magnetism of SmFe7 was studied by magnetic Compton scattering experiment with the synchrotron radiation along with those of SmFex (x = 2, 3) and Sm6 Fe23. Spin moment and orbital moment for SmFe7 were 6.60, and 7.20 μB/f.u., respectively. The magnetic Compton profile revealed that the spin moment of SmFe7 compounds consists of negative Sm moment and positive Fe moment. The comparison to other Sm-Fe crystals shows that the spin, orbital, and total moments increase linearly against a Fe/Sm ratio. [ABSTRACT FROM AUTHOR]

Anisotropies of spin-projected wave functions are measured on a Pd/Co multilayer system by measuring magnetic Compton profiles. The anisotropies of the wave functions are decomposed into the contributions of Co 3d states and Pd 4d states using an atomic model by a Hartree-Fock calculation assuming uniaxial (cylindrical) symmetry. Perpendicular anisotropy in Pd/Co multilayers is dominated by the anisotropy of Co 3d states; states with both magnetic quantum number |m|=2 and |m|=1 contribute. [ABSTRACT FROM AUTHOR]

The spin-polarized electron momentum density along the [100] direction of Eu(Fe0.89Co0.11)2As2 was measured using Magnetic Compton Scattering (MCS). Measurements were performed at different temperatures and applied external magnetic fields. These results provide the first direct insight into the orbital interactions that are responsible for the competing conductivity and ferromagnetism (FM) in this iron pnictide system. The orbital-wise decompositions of the density distribution show that at low applied magnetic field (0.1 T), the spin-polarized average Fe/Co-3d character is enhanced between 15 K and 19 K with a maximum at 17 K, the temperature at which the resistivity shows a local maximum, followed by re-entrant SC (superconducting)-like character. This clearly shows the dominance of the ferromagnetic character over conducting character in this temperature region where the resistivity shows a maximum. At higher applied magnetic field, we do not see this enhancement and subsequent collapse of the Fe/Co-3d character as the temperature decreases, consistent with the disappearance of the re-entrant SC-like feature at higher applied magnetic field. These data support a model in which the spin-polarization of the Fe/Co-3d orbitals is enhanced by the ferromagnetic Eu-ions, leading to the suppression of conductivity at ∼17 K (for 0.1 T), while at lower temperature the conductivity recovers and the Fe/Co-3d spin-polarization collapses. [ABSTRACT FROM AUTHOR]

The magnetic Compton profiles of Fe-50 at. % Rh intermetallic compound were measured to study the ferromagnetism induced by 200 MeV Xe ion irradiation. The magnetic effect at 50 K increases with increasing the ion-fluence. The analysis of the experimental result revealed that the values of spin moment induced by the irradiation were close to the values of magnetization obtained by a superconducting quantum interference device magnetometer, suggesting that the ion irradiation mainly induces the spin magnetic moment. The difference in magnetic Compton profiles between the irradiation-induced ferromagnetism and the intrinsic ferromagnetism in pure Fe is also discussed. [ABSTRACT FROM AUTHOR]