Observation of Tunneling Gap in Epitaxial Ultrathin Films of Pyrite-Type Copper Disulfide
Observation of Tunneling Gap in Epitaxial Ultrathin Films of Pyrite-Type Copper Disulfide
We report scanning tunneling microscopy investigation on epitaxial ultrathin films of pyrite-type copper disulfide.Layer by layer growth of CuS2 films with a preferential orientation of (111) on SrTiO3(001) and Bi2Sr2CaCu2O8+δ substrates is achieved by molecular beam epitaxy growth.For ultrathin films on both kinds of substrates, we observed symmetric tunneling gap …