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On the superconductivity of the Li$_{x}$RhB$_{y}$ compositions

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 نشر من قبل M. ElMassalami
 تاريخ النشر 2014
  مجال البحث فيزياء
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We observed superconductivity ($T_{c}$ $simeq$2-3 K) in Li$_{x}$RhB$_{y}$ intermetallics wherein $x$ and $y$ vary over a wide compositional range. The crystal structure consists of cubic unit-cell ($a$ $simeq$ 12.1 AA ) with centro-symmetric space group $Pnbar{3}n$. A weak but positive pressure-induced increase of $T_{c}$ was observed. The correlations between the composition and each of the followings were followed over a wide range of $x$ and $y$: the unit-cell dimensions, $T_{c}$ , Sommerfeld coefficient $gamma$, Debye temperature $theta_{D}$, and critical fields $H$$_{c1}$ and $H$$_{c2}$. The thermal evolution of the electronic specific heat within the superconducting phase was observed to follow a quadratic-in-$T$ behavior. In addition, a paramagnetic Meissner Effect (PME) is manifested during a low-field-cooled magnetization cycle. This manifestation of quadratic-in-$T$ behavior and PME feature will be discussed.

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