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Results of x-ray absorption studies of the structure of amorphous InSb are reported. We demonstrate that approximately 1% bond elongation in the amorphous phase (as compared to the crystalline phase) is accompanied by a counterintuitive increase (approximately 5%) in density. We argue that this controversy is due to the formation of wrong bonds in the amorphous phase with both Sb and In atoms effectively preserving their tetrahedral coordination. Our results additionally offer an alternative interpretation of the semiconductor-metal transition observed upon melting of InSb. [ABSTRACT FROM AUTHOR]

We have carried out a powder X-ray diffraction investigation on antiferromagnetic Kondo semiconductors CeRu2Al10 and CeOs2Al10 at low temperatures and under high pressures as well as the structural investigation on single crystal of these compounds. The results of powder X-ray studies of CeRu2Al10 and CeOs2A10 indicate that these compounds do not have structural transition at its antiferromagnetic ordering temperature. The results of single crystal structural refinement indicate that the b-axis of this crystal structure is insensitive not only to pressure but also to temperature and that the effect of cooling to Ce-Ce distance for CeRu2A10 is the same as that for CeOs2Al10. [ABSTRACT FROM AUTHOR]

We performed the 27AI NMR on CeRu2Al10 single crystal, which exhibits the unusual phase transition at T0 = 27 K. Below T0, the NMR lines split into two lines site-selectively depending on the magnetic-field direction. The NMR spectrum shows different types of splitting below and above H* ∼ 4 T for Hext || c where a metamagneticlike transition is observed. The results measured at resonance field of H0 ∼ 2.8 T were consistent with the antiferromagnetic ordered moment (mAF) parallel to the c axis proposed by neutron-scattering experiments. The results at H0 ∼ 4.4 T indicates that mAF || b is realized above H* for Hext || c, which was unexpected from the extremely small magnitude of ᵪb. As the origin of the unusual spin-flop transition from mAF || c to mAF || b at H*, we propose that the strong c-f hybridization along the a axis prevents mAF from aligning along the a axis, and mAF is confined to the bc plane. [ABSTRACT FROM AUTHOR]

We report on x-ray absorption studies of the structure of the liquid phase of a prototypical phase-change material Ge2Sb2Te5. We demonstrate that the local structure of liquid Ge2Sb2Te5 is very similar to that of amorphous Ge2Sb2Te5. Ge atoms in the liquid phase are found to be covalently bonded suggesting a semiconducting nature of the melt. [ABSTRACT FROM AUTHOR]

We studied the applied magnetic field direction (θ) dependence of the magnetic and transport properties of CeT2Al10 (T= Ru, Os) in the ab, bc, and ca planes focusing on the magnetic anisotropy in the ordered state. The magnetization of NdOs2Al10 was also studied as a reference of CeT2Al10. The results of NdOs2Al10 in the antiferromagnetic (AFM) state could be understood as a normal localized AFM compound. In CeT2Al10, the magnetic susceptibility in the ab, bc, and ca planes exhibits a smooth cosθ-like θ dependence both in the ordered state and the paramagnetic region. This suggests that the antiferromagnetic moment (mAFM) is not so strongly fixed along the c axis in the ordered phase, which indicates that the anisotropic AFM exchange interaction along the c axis is not strong and a coupling between the orbital moment of the Ce ion and the lattice is also small. The θ dependence of H* in the bc and ca planes strongly supports the spin-flop transition from mAFM∥c to mAFM∥b at H* for H∥c unexpected from the smallest magnitude of the magnetic susceptibility along the b axis, which was recently proposed by our 27Al NMR studies. From the θ dependence of H* in the ca plane, we propose that the phase II observed in a high-field magnetization curve a little below the critical field to the paramagnetic region for H∥a is the spin-flop phase B with mAFM∥b. H* in CeOs2Al10 is about twice larger than that in CeRu2Al10, and when the temperature approaches to the transition temperature (T0) from the low temperature, H* of CeOs2Al10 exhibits the unusual increase, but that of CeRu2Al10 is reduced. As the origin of the different behavior of H* in these two compounds, we propose that the relative weight of the singlet component against the AFM component in the ordered state close to T0 and also the c-f hybridization along the b axis are larger in CeOs2Al10 than in CeRu2Al10. We conclude that the anisotropic c-f hybridization is the origin of the unusual magnetic anisotropy of CeT2Al10 in the ordered state. [ABSTRACT FROM AUTHOR]

We have investigated the magnetic properties in the well localized compound NdFe2Al10 and the Kondo semiconductor Cer2Al10 (T = Ru, Os) to clarify the origin of the unusual magnetic order in Cer2Al10. In NdFe2Al10, the experimental results of the magnetic properties could be reproduced very well by the mean-field calculation for the two-sublattice model. In CeT2Al10 we could reproduce the anisotropic magnetic susceptibility in the paramagnetic region above 60-100 K very well by the mean-field calculation for the two-sublattice model introducing an anisotropic exchange interaction and the recently determined crystalline electric field (CEF) level scheme from Strigari et al. [Phys. Rev. B 86, 081105 (2012)]. However, in the antiferromagnetic (AFM) ordered state, we could not reproduce the experimental results at all in the framework of the mean-field calculation for the two-sublattice model. We propose that although the magnetic properties in the paramagnetic region above 60-100 K could be understood well by a localized picture, the ordered state could not, and that the c-f hybridization, especially along the a axis, is associated with the unusual magnetic order in CeT2Al10. [ABSTRACT FROM AUTHOR]