Hall effect and thermoelectric power in UNiGa

Abstract

We report on simultaneous measurements of the magnetization, magnetoresistance, Hall effect and thermo-electric power on single-crystal UNiGa to investigate the origin of giant magnetoresistance phenomena. The normal part of Hall coefficient is markedly different above and below the metamagnetic transition at low temperatures. The thermoelectric power at 4.2 K changes its sign between the two magnetic states. These results imply that the strong resistivity variations are intimately connected with a reconstruction of the Fermi surface across the transition. © 1996 The American Physical Society.