著者
Boero Mauro Oshiyama Atsushi Silvestrelli Pier Luigi
出版者
American Physical Society
雑誌
Physical review letters (ISSN:00319007)
巻号頁・発行日
vol.91, no.20, pp.206401, 2003-11
被引用文献数
27 22

The displacement of an oxygen atom in pure α quartz is studied via first-principles molecular dynamics. The simulations show that when an O atom in a Si-O-Si bridge is moved away from its original equilibrium position, a new stable energy minimum can be reached. Depending on the spin state and charge Q of the system, this minimum can give rise to either a threefold oxygen (singlet ground state and Q=+1) or to an unsaturated Si atom carrying a dangling bond (triplet state). In the latter case, the hyperfine parameters associated with the 29Si dangling bond are in rather good agreement with electron paramagnetic resonance/electron nuclear double resonance experiments.
著者
Boero Mauro Oshiyama Atsushi Silvestrelli Pier Luigi Murakami Kouichi
出版者
American Institute of Physics
雑誌
Applied physics letters (ISSN:00036951)
巻号頁・発行日
vol.86, no.20, pp.201910, 2005-05
被引用文献数
17 18

Recent experiments have shown that pure Si structures in a matrix of SiO2 can be formed by electron excitation techniques, with appealing applications in nanotechnology. Our ab initio simulations provide an insight into the underlying mechanism, showing that electron excitations weaken Si–O bonds in SiO2, dislodge O atoms and allow Si dangling bonds to reconstruct in stable Si–Si structures below the melting temperature. Differences in diffusivity of O (fast) and Si (slow) are shown to play a decisive role in the process.
著者
Boero Mauro Oshiyama Atsushi Silvestrelli Pier Luigi Murakami Kouichi
出版者
American Institute of Physics
雑誌
Applied physics letters (ISSN:00036951)
巻号頁・発行日
vol.86, pp.201910, 2005-05
被引用文献数
17

Recent experiments have shown that pure Si structures in a matrix of SiO2 can be formed by electron excitation techniques, with appealing applications in nanotechnology. Our ab initio simulations provide an insight into the underlying mechanism, showing that electron excitations weaken Si–O bonds in SiO2, dislodge O atoms and allow Si dangling bonds to reconstruct in stable Si–Si structures below the melting temperature. Differences in diffusivity of O (fast) and Si (slow) are shown to play a decisive role in the process.