On the electronic structure of an impurity band: a cumulant approach

摘要: The electronic structure of an impurity band in a heavily-doped semiconductor, the metallic regime just above Mott transition, is studied tight-binding scheme using cumulant expansion. density states shows no erosion its centre near level; result confirmed by detailed comparison between results obtained either numerical simulation technique or other analytical approaches. This also that within single-site framework, very different can be at extremities spectrum whereas converging are centre. Possible extensions to cases where short-range order effects important, such as liquid-metal systems, discussed.