Pressure Induced Superconductivity in the New Compound ScZrCo1-${\delta}$

Abstract

It is widely perceived that the correlation effect may play an important role in several unconventional superconducting families, such as cuprate, iron-based and heavy-fermion superconductors. The application of high pressure can tune the ground state properties and balance the localization and itineracy of electrons in correlated systems, which may trigger unconventional superconductivity. Moreover, non-centrosymmetric structure may induce the spin triplet pairing which is very rare in nature. Here, we report a new compound ScZrCo1-${\delta}$ crystallizing in the Ti2Ni structure with the space group of FD3-MS without a spatial inversion center. The resistivity of the material at ambient pressure shows a bad metal and weak semiconducting behavior. Furthermore, specific heat and magnetic susceptibility measurements yield a rather large value of Wilson ratio ~4.47. Both suggest a ground state with correlation effect. By applying pressure, the up-going behavior of resistivity in lowering temperature at ambient pressure is suppressed and gradually it becomes metallic. At a pressure of about 19.5 GPa superconductivity emerges. Up to 36.05 GPa, a superconducting transition at about 3.6 K with a quite high upper critical field is observed. Our discovery here provides a new platform for investigating the relationship between correlation effect and superconductivity.