AUTHORS:

Bogdanowicz R., Pyrchla K., Ficek M., Głowacki M.J., Skiba F., Ryl J., Gumieniak J., Tatarczak P., Sawczak M., Prześniak-Welenc M., Hänzi P., Heidt A., Wysmołek A., Buczyński R., Klimczak M.

ABSTRACT:

This study investigates the thermal decomposition mechanisms at silica-diamond interfaces following localised laser vitrification, combining experimental analysis with molecular dynamics simulations. Two types of diamond particles were analysed: nitrogen vacancy (NV)-rich nanodiamonds (180 nm) and monocrystalline synthetic diamonds (154 nm). The samples were fabricated using vacuum-based CO₂ laser vitrification at a wavelength of 10.6 μm, designed to overcome the processing temperature mismatch between diamond and silica. Scanning electron microscopy revealed distinct interface regions with localised defects measuring up to 10 μm in diameter in monocrystalline diamond samples. Raman spectroscopy and fluorescence analysis demonstrated a different decomposition for each diamond type, with NV-rich nanodiamonds exhibiting characteristic NV centre emission at 637 nm. Thermogravimetric analysis coupled with mass spectrometry identified a multi-step decomposition process, with CO₂ release occurring above 300 °C and distinct thermal degradation temperatures depending on the diamond type. Molecular dynamics simulations using the Reax Force Field method elucidated the interface dynamics, revealing that amorphous silica accelerates CO₂ release from carboxyl-functionalised diamond surfaces. These findings provide key insights into thermal decomposition at silica-diamond interfaces, contributing to the development of hybrid materials for quantum optics, particularly in low-loss magnetically sensitive optical fibres used in optomagnetometry.

Ceramics International, 2025, vol. 51 (27, part B), pp. 53796-53811, doi: 10.1016/j.ceramint.2025.09.123