A study was made of the coordination transformation of B3+ ions and the migration of Na+ and O2− ions in sodium borate glasses, induced by 250kHz, 800nm femtosecond laser irradiation. Micro-Raman spectra showed that the ratio of the integrated intensity of the 2 peaks at 806 and 774/cm first decreased and then increased with increasing distance from the center of the laser-modified zone. Electron dispersive X-ray spectra showed that a portion of the Na+ and O2− ions migrated from the vicinity of the focal point following femtosecond laser irradiation. A possible mechanism was proposed to explain the observed phenomena.

Femtosecond Laser Induced Coordination Transformation and Migration of Ions in Sodium Borate Glasses. Y.Liu, B.Zhu, L.Wang, J.Qiu, Y.Dai, H.Ma: Applied Physics Letters, 2008, 92[12], 121113