Stable local structure in LSMCO system and its relationship with pseudogap

Abstract

Pseudogap is a unique property of high-[Formula: see text] superconductors. However, it was also found that there is a similar pseudogap in giant magnetoresistive La–Sr–Mn–O materials, which are not superconductors. In our previous research, we suggested that the origin of the pseudogap is correlated with the stability of [Formula: see text] plane. We call it a steady “fixed triangle” local structure. If our assumption is correct, it will be expected to find a similar stable local structure in the La–Sr–Mn–O system, which is similar to the [Formula: see text] plane in cuprates. We synthesized Co-doped [Formula: see text] (LSMCO) materials and investigated them. Based on the detailed analysis of the crystalline structure, it is found that there indeed exists a stable local triangles in [Formula: see text] plane. Comparing this similarity with the fixed triangles in the cuprate superconductors, it shows that the origin of the pseudogap may possibly be correlated with the stability of the local structure.