TY - JOUR TI - Optical signatures of intrinsic electron localization in amorphous SiO2 AV - public Y1 - 2015/07/08/ EP - 6 KW - Science & Technology KW - Physical Sciences KW - Physics KW - Condensed Matter KW - Physics KW - electron traps KW - optical absorption KW - excited state KW - SELF-TRAPPED HOLES KW - SILICON DIOXIDE KW - GERMANIUM KW - QUARTZ KW - CENTERS KW - DENSITY KW - GLASSES KW - SURFACE KW - ATOMS N2 - We measure and analyse the optical absorption spectra of three silica glass samples irradiated with 1 MeV electrons at 80 K, where self-trapped holes are stable, and use ab initio calculations to demonstrate that these spectra contain a signature of intrinsic electron traps created as counterparts to the holes. In particular, we argue that optical absorption bands peaking at 3.7, 4.7, and 6.4?eV belong to strongly localised electrons trapped at precursor sites in amorphous structure characterized by strained Si?O bonds and O?Si?O angles greater than 132°. These results are important for our understanding of the properties of silica glass and other silicates as well as the reliability of electronic and optical devices and for luminescence dating. ID - discovery1479603 PB - IOP PUBLISHING LTD IS - 26 N1 - Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. VL - 27 JF - Journal of Physics: Condensed Matter A1 - El-Sayed, A-M A1 - Tanimura, K A1 - Shluger, AL UR - http://dx.doi.org/10.1088/0953-8984/27/26/265501 SN - 0953-8984 ER -