Possible field-induced quantum criticality in Ce₃Pd ₂₀Si₆

Ce₃Pd₂₀Si₆ forms in a cubic crystal structure with the cerium atoms located on two different sites, both of cubic point symmetry, resulting in two interleaved cubic cerium sublattices. We present here the results of detailed low-temperature specific heat and electrical resistivity measurements taken in magnetic fields up to 14 T, with the purpose of shedding light on the complex low-temperature behaviour that was alluded to in previous literature reports on this compound. Our specific heat data show two phase transitions, at T_L(B 0) 0.31 K and at T _U(B 0) 0.5 K respectively, probably of magnetic origin, and with distinctly different response to applied magnetic fields. T_L is shifted towards lower temperatures and becomes indiscernable in fields above 1 T. T_U on the other hand is shifted upward and disappears in fields above 8 T. The electrical resistivity data follow a Δρ T^5/3 power-law behaviour below T_U for a limited range in field, suggestive of spin fluctuations near a three-dimensional ferromagnetic quantum phase transition.