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Structural origin of light emission in germanium quantum dots.

ABSTRACT: We used a combination of optically-detected x-ray absorption spectroscopy with molecular dynamics simulations to explore the origins of light emission in small (5 nm to 9 nm) Ge nanoparticles. Two sets of nanoparticles were studied, with oxygen and hydrogen terminated surfaces. We show that optically-detected x-ray absorption spectroscopy shows sufficient sensitivity to reveal the different origins of light emission in these two sets of samples. We found that in oxygen terminated nanoparticles its the oxide-rich regions that are responsible for the light emission. In hydrogen terminated nanoparticles we established that structurally disordered Ge regions contribute to the luminescence. Using a combination of molecular dynamics simulations and optically-detected x-ray absorption spectroscopy we show that these disordered regions correspond to the disordered layer a few Å thick at the surface of the simulated nanoparticle.

SUBMITTER: Little W

PROVIDER: S-EPMC4260222 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Structural origin of light emission in germanium quantum dots.

Little W W Karatutlu A A Bolmatov D D Trachenko K K Sapelkin A V AV Cibin G G Taylor R R Mosselmans F F Dent A J AJ Mountjoy G G

Scientific reports 20141209

We used a combination of optically-detected x-ray absorption spectroscopy with molecular dynamics simulations to explore the origins of light emission in small (5 nm to 9 nm) Ge nanoparticles. Two sets of nanoparticles were studied, with oxygen and hydrogen terminated surfaces. We show that optically-detected x-ray absorption spectroscopy shows sufficient sensitivity to reveal the different origins of light emission in these two sets of samples. We found that in oxygen terminated nanoparticles i ...[more]

PMID: 25487681

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