Slow Electronic Dynamics in the Paramagnetic State of UTe₂

Anisotropic signatures of the electronic correlations in the electrical resistivity of UTe$_2$

“…Signatures of fluctuating magnetic moments µ a associated with a characteristic temperature T * 15−20 K were observed by NMR relaxation-rate measurements [33,46]. These fluctuations were found to develop progressively at temperatures below 30-40 K [46].…”

Magnetovolume Effect on the First-Order Metamagnetic Transition in UTe$_2$

“…59) Recently, a different characteristic energy scale T * ≈ 12 K was also proposed. 51,[60][61][62][63] A broad peak-like anomaly appeared at T * in some thermodynamic quantities. 51) NMR studies for H || a have revealed some anomalies at both of T max χ and T * ; starting a broadening of NMR spectra below T max χ and a peak in the nuclear spinspin relaxation rate at T * .…”

“…51) NMR studies for H || a have revealed some anomalies at both of T max χ and T * ; starting a broadening of NMR spectra below T max χ and a peak in the nuclear spinspin relaxation rate at T * . 63) Thus, T * may correspond to the short-range ordering temperature. Interestingly, Γ H is almost identical to Γ T at T * .…”

Superconducting order parameter in UTe$_2$ determined by Knight shift measurement

“…16) The normal-state K a obtained in the present measurement is consistent with that reported in a recent study. 17) For reliable low-temperature NMR measurements down to 75 mK, the crystal with the NMR coil was immersed in a 3 He/ 4 He mixture, and the energy of the RF pulses was reduced to ensure that the NMR results were unchanged by the power of the RF pulses. Furthermore, we experimentally confirmed the superconductivity just after the NMR RF pulses using a technique reported in a previous study 10,18) .…”

“…This is due to the anomalous broadening of the NMR line-width below 20 K, as reported recently. 17) The small SC diamagnetic effect was evaluated with the penetration depth for H a. 21) Figure 3(a) shows the T dependence of K a determined by the peak position of the NMR spectrum in Fig.…”