To investigate the normal-state magnetic properties of ${\mathrm{UTe}}_2$ under pressure, we perform ${}^{125}\mathrm{Te}$ nuclear magnetic resonance (NMR) measurements up to 2 GPa. Below 1.2 GPa, the $b$-axis NMR Knight shift shows a broad maximum at the so-called $T_{{\chi }_{\max }}$ on cooling, which is consistent with the magnetization measurement under pressure. $T_{{\chi }_{\max }}$ decreases with increasing pressure and disappears at the critical pressure $P_{\mathrm{c}}$ = 1.7 GPa, above which superconductivity is destroyed. This tendency is also observed in the temperature dependence of the nuclear spin-lattice relaxation rate $1/T_1$. At low pressures, $1/T_1$ shows a conventional Fermi-liquid behavior ($1/T_{1}T=\mathrm{const}$) at low temperatures, indicating the formation of the heavy-fermion state. Above $P_{\mathrm{c}}$, $1/T_{1}T$ follows a $1/T$ behavior without any crossover to the heavy-fermion state down to the lowest temperature ($\sim 3$ K). In addition, the NMR signals disappear below 3 K, due to the influence of the magnetically ordered moments. From the pressure dependence of the $T_{{\chi }_{\max }}$ and Knight shift, it was found that the Fermi surface character is abruptly changed at $P_{\mathrm{c}}$, and that superconductivity is observed only in the heavy-fermion state.

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• Electronic structure
• Kondo effect
• Magnetic anisotropy
• Magnetism
• Pairing mechanisms
• Spin-triplet pairing
• Ferromagnetic superconductors
• Strongly correlated systems
• Topological superconductors
• Nuclear magnetic resonance
• Pressure techniques