  The group IB impurities (Cu, Ag, and Au) incorporated into II-VI zinc blende
hosts of ZnTe and CdTe exhibit well resolved excitation lines followed by a
photoionization continuum in their infrared absorption spectra. They are
associated with transitions from a "1s-like" ground state to various "p-like"
excited state characteristic of a hole bound to a Coulomb center. Their spacing
agree well with those predicted in the effective mass theory for single
acceptors as expected for group IB elements substitutionally replacing the
group IIB cations of the host. The occurrence of the simultaneous excitation of
the Lyman transitions in combination with the zone center longitudinal optical
phonon and hence lying in the photoionization continuum and displaying
Fano-like asymmetries are features described and interpreted.
