AC magnetic-susceptibility studies on superconducting UTe₂

UTe₂ has recently attracted enormous attention as a spin-triplet superconductor candidate. Several intriguing properties have been observed in UTe₂, such as multiple pressure-induced superconducting and magnetic phases as well as re-entrant superconductivity under applied magnetic field [1]. Importantly, the superconducting properties of UTe₂ at ambient conditions crucially depend on the details of crystal growth. For instance, both the superconducting transition temperature and the residual specific heat coefficient drastically vary among crystals grown in different conditions despite having very similar structural properties [2-4]. Here, we investigate UTe₂ samples with a range of values of T_c using ac magnetic-susceptibility measurements, which reveal the vortex dynamics in the superconducting state. We also re-visit the pressure-temperature phase diagram of UTe₂ by means of ac magnetic-susceptibility measurements under hydrostatic pressure and investigate pressure-induced superconducting and magnetic phases in the vicinity of the critical pressure.



[1] D. Aoki et al. J. Phys.: Condens. Matter 34 243002 (2022).

[2] Y. Haga et al. J. Phys. Condens. Matter 34, 175601 (2022).

[3] P. F. S. Rosa et al. Commun Mater 3, 33 (2022).

[4] A. Weiland et al. J. Phys. Mater. 5 044001 (2022).