with Unique Mn-cluster Columns*

Quasi-one-dimensional material consists of one-dimensional structural units which are weakly coupled with each other to form a three-dimensional structure. This structural feature may host interesting states including charge-density-wave and spin-density-wave orders. Recently we have discovered a new quasi-one-dimensional material KMn₆Bi₅ with unique Mn-cluster columns. It is crystallized in a monoclinic crystal structure and consists of [Mn₆Bi₅]⁻ columns which are charge-balanced by K. Resistivity, specific heat and magnetization measurements support that it has an antiferromagnetic order at ~ 75 K with short-range spin correlations above the ordering temperature. Resistivity perpendicular to the columns exhibits an incoherent-to-coherent crossover at ~ 40 K, indicating a quasi-one-dimensional electronic property. Detailed structural and transport properties of this compound will be presented in this talk. Our search for emerging superconductivity in this compound by suppressing antiferromagnetism through chemical doping will also be presented.