Samarium hexaboride is a candidate for the topological Kondo insulator state, in which Kondo coherence is predicted to give rise to an insulating gap spanned by topological surface states. Here we investigate the surface and bulk electronic properties of magnetically alloyed Sm 1-x M x B 6 (M=Ce, Eu). Remarkably, in-gap surface states visible to angle-resolved photoemission spectroscopy (ARPES) and resistivity features associated with Kondo coherence are both found to persist in highly modified samples with up to 30% Sm substitution. The results are interpreted in terms of a hierarchy of energy scales, in which surface state emergence is linked to the relatively robust formation of a direct Kondo gap.

Uranium compounds can manifest a wide range of fascinating many-body phenomena, and are often thought to be poised at a crossover between localized and itinerant regimes for 5f electrons. The antiferromagnetic dipnictide USb2 has been of recent interest due to the discovery of rich proximate phase diagrams and unusual quantum coherence phenomena. Here, linear-dichroic X-ray absorption and elastic neutron scattering are used to characterize electronic symmetries on uranium in USb2 and isostructural UBi2. Of these two materials, only USb2 is found to enable strong Hund’s rule alignment of local magnetic degrees of freedom, and to undergo distinctive changes in local atomic multiplet symmetry across the magnetic phase transition. Theoretical analysis reveals that these and other anomalous properties of the material may be understood by attributing it as the first known high temperature realization of a singlet ground state magnet, in which magnetism occurs through a process that resembles exciton condensation.

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Abstract-Since its invention in the turn of 20 th century, semiconductors have always riddled the minds of contemporary science. The various properties of the semiconductors have been studied using spectroscopy, Hall Effect experiment or simple measurement methods under different conditions. The behavior observed has led to a different aspect and hence a different application. The aim of this paper is to study the properties of a semi-conductor bar specially the magneto-resistance, carrier concentration, Energy band gap and the effect of magnetic field on Hall coefficient using a new experimental setup and also discuss its application. Another objective of this paper has been validating the Drude's Model and proposing a solution to the Hall Effect drawback. The design can be used as a replacement to the Hall Effect experiment where as it incorporates the magnetic field's effect for the Hall co-efficient. This experiment employs only magnetic field to determine the magneto resistance unlike Hall Effect where along with magnetic field electric field is also used.

We compute the spin excess for the neutrinos radiated in the process of electron capture beta decay of partially polarized nuclei. The results of computation are presented for the 119 Sb nuclei polarized by the strong hyperfine field in a ferromagnetic substance. This system was suggested as a possible source of directed neutrino radiation. We directly compute the spin excess of radiated neutrinos and show that it is greater than that estimated previously under simplifying assumptions.

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