Anisotropic Electrical Transport in the Heavy Fermion Compound alpha -YbAlB sub( 4)

We studied the electrical transport properties of the heavy fermion compound alpha -YbAlB ... , an isostructural polymorph of the Yb-based heavy fermion superconductor beta -YbAlB ... . The magnetic part of the a b -plane resistivity of alpha -YbAlB ... , ... , is about four times larger than ... along the c -axis at 300 K. With decreasing temperature, the ratio ... increases and reaches ~ 9, forming a peak at around 10 K. In contrast, alpha -LuAlB ... shows almost temperature independent anisotropy ... ~ 3.5. These observations indicate that the hybridization between 4 f and conduction electrons is the origin of the enhanced anisotropy in the resistivity of ...-YbAlB ... at low temperatures. (ProQuest: ... denotes formulae/symbols omitted.)