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In this report, we study temperature dependent heat capacity and electrical resistance of Tb1-xHoxMn2Si2 (x = 0.5). Two successive low temperature magnetic transitions T1 (∼15 K) and T2 (∼25 K) are observed from both measurements. Anomalous rise in heat capacity at low temperatures is ascribed to the nuclear Schottky effect. Sommerfeld coefficient (γ), Debye temperature (θD) and density of states at Fermi level N(EF) is calculated from the zero field specific heat data. We observe 4f contribution to heat capacity from T1 to 100K, which is attributed to crystal field effect. In the electrical transport study, application of the magnetic field shows a substantial change around the ordering temperature of rare earth moment resulting in large positive magnetoresistance of about 20% with field change of 6T.

Temperature and field dependent magnetization and resistivity of TbMn2Si2 have been studied. Two first order magnetic transitions at Tc1 = 52 K and Tc2 = 64 K are observed in both the measurements. The rise in resistivity at Tc2 with decrease in temperature is attributed to large difference in the periodicity of magnetic and crystallographic lattice. Resistivity fits at low and relatively higher temperatures give good account of the data. These fits further suggest the role of spin fluctuations in the antiferromagnetic region. Magnetoresistance calculated from in-field resistivity data, up to 8 T, shows switching from positive to negative to positive values with temperature.