Donor-like excited states of exciton bound to neutral acceptor in ZnTe

Photoexcitation spectroscopy has been used to study the excited states of the neutral c-acceptor bound exciton complex A^c₁ in ZnTe. We have detected four excited states at ～ 11.2 meV above the bound exciton ground state. Zeeman effects on these excited states have also been studied. The results show that they correspond to excitations of the bound electron to donor-like 2p and 2s orbital states. This represents an unambiguous experimental evidence of the pseudo-donor model previously suggested by Rühle and Bimberg for acceptor bound exciton complexes when m_e ? m_h.