Phys. Rev. B 73, 132302 (2006) [4 pages]Photoluminescence quantum efficiency of dense silicon nanocrystal ensembles in SiO2Received 13 September 2005; revised 27 February 2006; published 28 April 2006 The photoluminescence decay characteristics of silicon nanocrystals in dense ensembles fabricated by ion implantation into silicon dioxide are observed to vary in proportion to the calculated local density of optical states. A comparison of the experimental 1∕e photoluminescence decay rates to the expected spontaneous emission rate modification yields values for the internal quantum efficiency and the intrinsic radiative decay rate of silicon nanocrystals. A photoluminescence quantum efficiency as high as 59%±9% is found for nanocrystals emitting at 750 nm at low excitation power. A power dependent nonradiative decay mechanism reduces the quantum efficiency at high pump intensity. © 2006 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevB.73.132302
DOI:
10.1103/PhysRevB.73.132302
PACS:
78.67.Bf, 78.55.−m
|
|
About | Terms and Conditions | Subscriptions | Search | Help
Use of the American Physical Society websites and journals implies that the user has read and agrees to our Terms and Conditions and any applicable Subscription Agreement. Physical Review®, Physical Review Letters®, Reviews of Modern Physics®, and Physical Review Special Topics® are trademarks of the American Physical Society.