Superconductivity coexisting with ferromagnetism in a quasi-one dimensional non-centrosymmetric (TaSe4)3I

Abstract

Low-dimensional materials with broken inversion symmetry and strong spin-orbit coupling can give rise to fascinating quantum phases and phase transitions. Here we report coexistence of superconductivity and ferromagnetism below 2.5 K in the quasione dimensional crystals of non-centrosymmetric (TaSe4)3I (space group: P¯421c). The unique phase is a direct consequence of inversion symmetry breaking as the same material also stabilizes in a centro-symmetric structure (space group: P4/mnc) where it behaves like a non-magnetic insulator[1–4]. The coexistence here upfront contradicts the popular belief that superconductivity and ferromagnetism are two apparently antagonistic phenomena. Notably, here, for the first time, we have clearly detected Meissner effect in the superconducting state despite the coexisting ferromagnetic order. The coexistence of superconductivity and ferromagnetism projects non-centrosymmetric (TaSe4)3I as a host for complex ground states of quantum matter including possible unconventional superconductivity with elusive spin-triplet pairing[5–8].

Spin-reorientation driven emergent phases and unconventional magnetotransport in quasi-2D vdW ferromagnet Fe4GeTe2

“…Note added: After our submission 94 , a recent work 95 focusing only on the AHE in a bulk Fe 4 GeTe 2 single crystal is reported.…”