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Abstract: We have studied the orientation and magnetic properties of FePt and CoPt films deposited by electron-beam co-evaporation on MgO(110) single-crystal substrates at substrate temperatures from 500 to 700°C. We observed that long-range chemical ordering of the L10 structure occurred over the entire range of substrate temperatures in FePt films and at 600°C and up in CoPt films. Growth of FePt and CoPt yielded epitaxial films with cube-on-cube orientation of the pseudo-cubic L10 lattice with respect to the cubic MgO. X-ray diffraction patterns and magnetization loops of the FePt and CoPt films revealed the existence of L10 domains with the tetragonal c axis inclined at 45° to the film plane, orientations (0 h h) and (h 0 h), as well as L10 domains with the tetragonal c axis in the plane of the film, orientation (h h 0). The FePt and CoPt films for which X-ray diffraction indicated tetragonal phase was present all exhibited hard magnetic properties with easy axis along the [001] substrate direction as well as large in-plane magnetocrystalline anisotropy. [Copyright &y& Elsevier]

We have constructed a high-resolution synchrotron-radiation angle-resolved photoemission (ARPES) spectrometer combined with a combinatorial laser molecular-beam epitaxy (laser MBE) thin film growth system in order to investigate the electronic structure of transition metal oxide thin films. An ARPES spectrometer GAMMADATA SCIENTA SES-100 was selected for the high-throughput and high-energy and angular-resolution ARPES measurements. A total energy resolution of 6.3 meV and a momentum (an angular) resolution of 0.02 Å[SUP-1] (0.2°) were obtained at a photon energy of 40 eV. The system is installed at the high-resolution vacuum-ultraviolet beamline BL-1C or the soft-x-ray undulator beamline BL-2C at the Photon Factory as an end-station. Another distinctive feature of this system is the direct connection from the spectrometer to a laser MBE chamber. Thin film samples can be transferred quickly into the photoemission chamber without breaking ultrahigh vacuum. Laser MBE is one of the best methods to grow thin films of many different transition metal oxides and to achieve well-ordered surfaces, which are indispensable for the ARPES measurements. The capabilities of the system and the importance of the in situ sample transfer between ARPES and laser MBE are demonstrated by studying the band structure of La[SUB0.6]Sr[SUB0.4]MnO[SUB3] thin films epitaxially grown on SrTiO[SUB3] substrates by laser MBE. [ABSTRACT FROM AUTHOR]

Immunomodulatory drugs (IMiDs) thalidomide, lenalidomide (Len) and pomalidomide trigger anti-tumor activities in multiple myeloma (MM) by targetting cereblon and thereby impacting IZF1/3, c-Myc and IRF4. Histone deacetylase inhibitors (HDACi) also downregulate c-Myc. We therefore determined whether IMiDs with HDACi trigger significant MM cell growth inhibition by inhibiting or downregulating c-Myc. Combination treatment of Len with non-selective HDACi suberoylanilide hydroxamic acid or class-I HDAC-selective inhibitor MS275 induces synergic cytotoxicity, associated with downregulation of c-Myc. Unexpectedly, we observed that decreased levels of cereblon (CRBN), a primary target protein of IMiDs, was triggered by these agents. Indeed, sequential treatment of MM cells with MS275 followed by Len shows less efficacy than simultaneous treatment with this combination. Importantly ACY1215, an HDAC6 inhibitor with minimal effects on class-I HDACs, together with Len induces synergistic MM cytotoxicity without alteration of CRBN expression. Our results showed that only modest class-I HDAC inhibition is able to induce synergistic MM cytotoxicity in combination with Len. These studies may provide the framework for utilizing HDACi in combination with Len to both avoid CRBN downregulation and enhance anti-MM activities.

We report on the fabrication of terminating-layer-controlled La[sup 0.6]Sr[sup 0.4]MnO[sup 3] (LSMO) thin films and in situ characterization of the films using photoemission spectroscopy. The terminating layer of the LSMO films was changed from B to A site by inserting one atomic layer of SrO between the LSMO film and a TiO[sub 2]-terminated SrTiO[sub 3] (001) substrate. The successful control of the terminating layer was confirmed by measuring the angular dependence of core-level spectra. Detailed analysis of the Sr 3d core levels revealed considerable differences in chemical bonding states of Sr atoms in the surface regions of films with different terminating layers. [ABSTRACT FROM AUTHOR]

Epitaxial thin films of pyrochlore-type ferromagnetic molybdates Sm[sub 2]Mo[sub 2]O[sub 7], as a geometrically spin-frustrated system, were fabricated by a pulsed-laser deposition. The temperature gradient method combined with the concurrent x-ray diffraction method was exploited for high throughput optimization of the film quality. The excess supply of Mo for compensating the volatile Mo-related species improved the crystallinity. The resistivity and magnetization of the optimized film were 3 mΩ cm and 0.8 µ[sub B]/Mo at 10 K, respectively, being similar to those of a single crystal. The observed finite anomalous Hall term that persists down to the lowest temperature reflects an appearance of spin chirality in this spin-frustrated system. [ABSTRACT FROM AUTHOR]

In this paper we review a variety of spectra for Ce compounds, i.e. valence photoemission and inverse valence photoemission, core-level and resonant photoemission as well as X-ray absorption, X-ray emission and X-ray magnetic circular dichroism (MCD). Those spectra are theoretically analysed by using the single-site Anderson model with various final state interactions. In the first part of the present article we are considering intermetallic Ce compounds, especially several Ce–Pd ordered phases, as well as CeRh3, CeSn3 and CeFe2. In the second part we focus on insulating Ce compounds like CeF3 as well as related systems like Ce oxides. Also we compare Ce hydroxides to other rare-earth hydroxides. Discussions are given on the physical information derived from the analysis, especially through a few key parameters of an extended version of the previously considered Anderson model. Those parameters (i.e. the Coulomb interaction Ufd between 5d and 4f electrons as well as the core hole potential -Udc acting on the 5d electron) have necessarily to be taken into account in order to interpret the experimental L3 X-ray absorption spectra. Another important point stressed in the present paper is the surface/bulk sensitivities of the various spectra to be investigated and theoretically analysed. Also similarities and differences in spectral features between metallic and insulating systems are pointed out. [ABSTRACT FROM AUTHOR]

We report on an in situ synchrotron-radiation photoemission study of terminating layer controlled La0.6Sr0.4MnO3 thin films grown on SrTiO3 (0 0 1) substrates by laser molecular beam epitaxy. The high-resolution Sr 3d core-level spectra show noticeable and quantitative differences. Detailed analysis of the Sr 3d core levels revealed considerable differences in chemical bonding states of Sr atoms in the surface regions of films with different terminating layers. [Copyright &y& Elsevier]

We have constructed a high-resolution photoelectron spectroscopy system combined with a laser molecular beam epitaxy (laser-MBE) chamber and have characterized composition-controlled La1-xSrxMnO3 (LSMO) thin films. The importance of atomically flat surfaces by in situ photoelectron spectroscopy for revealing the intrinsic electronic structures has been demonstrated by comparing O1s, O2s and valence band spectra from the laser-MBE-grown LaMnO3 and LSMO films with those from the scraped samples. Even for the laser-MBE-grown LSMO films, core levels and band structure exhibit strong dependence on surface morphology. For atomically flat LSMO films, we have also elucidated the hole-doping features into Mn3d eg band by substituting La with Sr by resonant photoelectron spectra. [Copyright &y& Elsevier]