抄録
Photon-stimulated desorption of excited-state alkali atoms from sodium and potassium halides has been investigated by using a strong quasi-monochromatic undulator-radiation from an electron storage-ring as a light source. The atomic emission (Na D-line) due to the transition from desorbed excited-state sodium atoms is stronger in NaF than in NaCl, and is too weak to be observed in NaBr and NaI, while the intensity of the atomic emission line from excited-state potassium atoms is larger in the order of KI, KBr and KCl. This result corresponds well with the recent models of the defect formation and the intrinsic luminescence, and is interpreted in terms of the lattice instability due to the electronic excitation in the surface layer.