Dynamical behavior and comprehensive vortex phase diagram in a 2D superconductor

Two-dimensional (2D) superconductors exhibit novel aspects that are distinct from those of the 3D counterparts. Recent advances have developed methods to produce ideal 2D electron systems, which enable us to investigate the intrinsic properties of clean 2D superconductors [1]. In this talk, we focus on vortex matter in gate-induced 2D superconductors. In addition to the magnetic-field induced quantum metallic state in an equilibrium state, which has been never seen in 3D superconductors where the ground state is vortex solid, we found a unique dynamical behavior of 2D vortices under large current in gated MoS₂ [2]. We constructed a comprehensive vortex phase diagram combined with previous results, which we believe captures the intrinsic nature of vortex states in clean 2D superconductors.
[1] Y. Saito et al., Nat. Rev. Mater. 2, 16094 (2016). [2] Y. Saito et al., Phys. Rev. Mat. 4, 074003 (2020).