Magnetic field-induced quantum critical point in YbPtIn and YbPt${}_{0.98}$In single crystals

Abstract

Detailed anisotropic (H$\parallel$ab and H$\parallel$c) resistivity and specific heat measurements were performed on online-grown YbPtIn and solution-grown YbPt${}_{0.98}$In single crystals for temperatures down to 0.4 K, and fields up to 140 kG; H$\parallel$ab Hall resistivity was also measured on the YbPt${}_{0.98}$In system for the same temperature and field ranges. All these measurements indicate that the small change in stoichiometry between the two compounds drastically affects their ordering temperatures (T${}_{ord}\approx 3.4$ K in YbPtIn, and $\sim 2.2$ K in YbPt${}_{0.98}$In). Furthermore, a field-induced quantum critical point is apparent in each of these heavy fermion systems, with the corresponding critical field values of YbPt${}_{0.98}$In (H${}_c^{ab}$ around 35-45 kG and H${}_c^c\approx 120$ kG) also reduced compared to the analogous values for YbPtIn (H${}_c^{ab}\approx 60$ kG and H${}_c^c>140$ kG)