Metamagnetism, sign reversal and low temperature magnetocaloric effect in single-crystalline EuV2Al20

Highlights: • Frank-Kasper compound EuV₂Al₂₀ studied using the M(H) and CP(T,H) measurements. • The compound shows AFM ordering at 5.6 K. • The system exhibits a weak metamagnetic transition for the field value ∼1 T. • Moderate magnetocaloric effect was estimated from Maxwell's relations. • The maximum entropy change was observed to be 8.4 J/mol.K (7T). • The adiabatic temperature change was estimated to be 5.5 K (7T). • 'S' shaped curved of Arrott Plots indicate weak metamagnetic behavior. • Dispersion in the universal scaling point towards a weak metamagnetic behavior. The Frank-Kasper cage compound EuV₂Al₂₀ crystallizes in the cubic structure with $\mathrm{Fd}\bar{3}m$ space group and exhibits unusual magnetic and transport properties. The system undergoes an antiferromagnetic transition below 5.6 K wherein the Eu²⁺ moments are aligned anti-parallel along 1 1 1 direction and the system exhibits a weak metamagetic transition at the field of 1 T. Arrott plots ($M^2$ vs $H/M$) show a "S" shaped variation in the low fields below $T_N$ and the plausible reason for the occurrence of negative slope is discussed. Isothermal magnetic entropy change is estimated from both magnetization and heat capacity measurements invoking the Maxwell's thermodynamic relations. Temperature variation of $\Delta S_m$ showed a weak negative minimum and a sign reversal at the field value of 1 T due to field induced metamagnetic transition. Universal master curve is constructed by rescaling the $\Delta S_m$ vs T curves in the context of analysing the nature of the magnetic transition.