Femtosecond spectroscopy of defect modes in silica glasses
Résumé
The D1 and D2 defect modes are investigated in the time domain in normal and densified silica using a high sensitivity femtosecond pump-probe technique with 15 fs pulses. Their frequency and width are precisely determined even when they are partly masked by a broad background in spontaneous Raman spectroscopy. These results open up many possibility for investigation of local structures in glasses.