Nonlinear paramagnetic magnetization in the mixed state of CeCoIn_5

TL;DR

This study investigates the nonlinear paramagnetic magnetization behavior in the mixed state of CeCoIn_5, revealing a distinct power-law dependence and anomalous magnetization features due to combined orbital and Pauli effects.

Contribution

It provides the first detailed experimental evidence of nonlinear paramagnetic magnetization in CeCoIn_5's mixed state, highlighting the interplay of orbital and Pauli limiting effects.

Findings

Paramagnetic torque scales as H^{2.3} in the mixed state.

Magnetization exhibits anomalous behavior after subtracting paramagnetic contributions.

Both H∥c and H∥ab axes show nonlinear paramagnetic responses.

Abstract

Torque and magnetization measurements in magnetic fields $H$ up to 14 T were performed on CeCoIn$_5$ single crystals. The amplitude of the paramagnetic torque shows an $H^{2.3}$ dependence in the mixed state and an $H^{2}$ dependence in the normal state. In addition, the mixed-state magnetizations for both $H\parallel c$ and $H\parallel ab$ axes show anomalous behavior after the subtraction of the corresponding paramagnetic contributions as linear extrapolations of the normal-state magnetization. These experimental results point towards a nonlinear paramagnetic magnetization in the mixed state of CeCoIn$_5$, which is a result of the fact that both orbital and Pauli limiting effects dominate in the mixed state.