We observed the donor-assisted infrared absorption of Li acceptor in bulk Z
nSe. Two kinds of donors, Li-int and/or Ga-Zn, make transition from 1S to 2
S state during photo-excitation of Li acceptor. The transition energies are
estimated at 6.3 and 20.2 meV for Li-int and Ga-Zn, respectively. Fano res
onances of the valence band state with the simultaneous excited states of a
Li acceptor and donors were also observed. (C) 2001 Elsevier Science B.V.
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