Interfacial disorder and optoelectronic properties of diamond nanocrystals
Journal
Physical Review B
Date Issued
July 15, 2009
DOI
10.1103/PhysRevB.80.045307
Abstract
We present in this work a theoretical framework based on the tight-binding method, which is able to probe
at a local atomic level the optoelectronic response of nanomaterial systems and link it to the associated
disorder. We apply this methodology to carbon nanocomposites containing diamond nanocrystals. We find that
significant structural and topological disorder exists at the interface between the nanodiamonds and the embedding
amorphous carbon matrix. This can be quantitatively probed by extracting the Urbach energies from
the optical parameters. Disorder in the nanocrystals appears in their outer shell near the interface and is
manifested as bond length and angle distortions. Energetics and stability analysis show that nanodiamonds
embedded in matrices with high density and high fraction of fourfold coordinated atoms are more stable.
at a local atomic level the optoelectronic response of nanomaterial systems and link it to the associated
disorder. We apply this methodology to carbon nanocomposites containing diamond nanocrystals. We find that
significant structural and topological disorder exists at the interface between the nanodiamonds and the embedding
amorphous carbon matrix. This can be quantitatively probed by extracting the Urbach energies from
the optical parameters. Disorder in the nanocrystals appears in their outer shell near the interface and is
manifested as bond length and angle distortions. Energetics and stability analysis show that nanodiamonds
embedded in matrices with high density and high fraction of fourfold coordinated atoms are more stable.