Inverse photoemission study of Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/

An inverse photoemission spectrum of Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/ is presented. The spectrum shows a clear Fermi-edge structure in contrast to those reported for YBa/sub 2/Cu/sub 3/O/sub 7/ and La/sub 1.8/Sr/sub 0.2/CuO/sub 4/, giving direct evidence for the existence of the Fermi-liquid states in Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/.