Sharp-line donor-acceptor pair spectra in AlSb

We have observed sharp-line donor-acceptor pair spectra (type I) in Se-doped AlSb. We analyze the spectra quantitatively by using a known solution of the Schrödinger equation for an electron bound to a dipole of finite charge separation. Excellent agreement is obtained between the theoretically predicted and experimentally observed spectra for the parameters Eg=1.69 eV, ED=0.15 eV, EA=0.04 eV, and an electron Bohr radius ae=4.28. © 1968 The American Physical Society.