Modulated magnetism and anomalous electronic transport in Ce sub(3) Cu sub(4) As sub(4) O sub(2)

The complex magnetism and transport properties of tetragonal Ce sub(3) Cu sub(4) As sub(4) O sub(2) were examined through neutron scattering and physical property measurements on polycrystalline samples. The lamellar structure consists of alternating layers of CeCu sub(4) As sub(4) with a single square Ce lattice and Ce sub(2) O sub(2) bilayers. Peaks in the specific heat at the Neel temperature T sub()N24 K, T sub(2)=16 K, and T sub(3)=1.9 K indicate three magnetic phase transitions or distinct crossover phenomena. For T