Magnetic field driven quantum critical phase transition in Ce$₃$Al

The resistivity and heat capacity of CeAl, a well-known Kondo system, is probed under high magnetic fields of up to 14 T. The system is known to undergo a first-order structural phase transition from hexagonal to monoclinic phase at 110 K. The current study has revealed that this structural transition is a robust one under high magnetic fields. However, clear dispersion in resistivity and heat capacity are seen in the presence of high magnetic fields below 30 K, whose analysis suggest its nearness to quantum critical point (QCP). Systematic vanishing of Kondo ordering ( behaviour) and the appearance of non-Fermi liquid behaviour (+ behaviour) around 6–9 T region at low temperatures suggest that the system settles for a QCP. In line with the resistivity, the heat capacity also revealed signatures reminiscent of a non-Fermi liquid. The first-time confirmation about the existence of a QCP in stoichiometric CeAl makes this already-known compound more interesting because it could lead to the discovery of possible new ground states.