Specific heat in high magnetic fields and magnetic phase diagram of CePt$_2$In$_7$

TL;DR

This study investigates the specific heat and magnetic phase diagram of CePt₂In₇ under high magnetic fields, revealing a possible field-induced quantum critical point and insights into its electronic and magnetic structure.

Contribution

It provides detailed specific heat measurements in high magnetic fields, revealing the magnetic phase diagram and evidence for a quantum critical point in CePt₂In₇.

Findings

Suppressed Néel temperature with magnetic field along c-axis.

Field-induced quantum critical point near 60 T.

Evidence for anisotropic spin-density wave and two-dimensional electronic structure.

Abstract

We report specific heat measurements on a high quality single crystal of the heavy-fermion compound CePt$_2$In$_7$ in magnetic fields up to 27 T. The zero-field specific heat data above the N\'{e}el temperature, $T_N$, suggest a moderately enhanced value of the electronic specific heat coefficient $\gamma = 180 \; \rm{mJ/K^2mol}$. For $T<T_N$, the data at zero applied magnetic field are consistent with the existence of an anisotropic spin-density wave opening a gap on almost entire Fermi surface, suggesting extreme two-dimensional electronic and magnetic structures for CePt$_2$In$_7$. $T_N$ is monotonically suppressed by magnetic field applied along the $c$-axis. When field is applied parallel to the $a$-axis, $T_N$ first increases at low field up to about 10 T and then decreases monotonically at higher field. Magnetic phase diagram based on specific heat measurements suggests that a field-induced quantum critical point is likely to occur slightly below 60 T for both principal orientations of the magnetic field.