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Intense visible and near-infrared upconversion photoluminescence in colloidal LiYF?:Er³+ nanocrystals under excitation at 1490 nm.

ABSTRACT: We report intense upconversion photoluminescence (PL) in colloidal LiYF(4):Er(3+) nanocrystals under excitation with telecom-wavelength at 1490 nm. The intensities of two- and three-photon anti-Stokes upconversion PL bands are higher than or comparable to that of the Stokes emission under excitation with low power density in the range 5-120 W/cm(2). The quantum yield of the upconversion PL was measured to be as high as ?1.2 ± 0.1%, which is almost 4 times higher than the highest upconversion PL quantum yield reported to date for lanthanide-doped nanocrystals in 100 nm sized hexagonal NaYF(4):Yb(3+)20%, Er(3+)2% using excitation at ?980 nm. A power dependence study revealed that the intensities of all PL bands have linear dependence on the excitation power density, which was explained by saturation effects in the intermediate energy states.

SUBMITTER: Chen G

PROVIDER: S-EPMC3430509 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Intense visible and near-infrared upconversion photoluminescence in colloidal LiYF₄:Er³+ nanocrystals under excitation at 1490 nm.

Chen Guanying G Ohulchanskyy Tymish Y TY Kachynski Aliaksandr A Agren Hans H Prasad Paras N PN

ACS nano 20110513 6

We report intense upconversion photoluminescence (PL) in colloidal LiYF(4):Er(3+) nanocrystals under excitation with telecom-wavelength at 1490 nm. The intensities of two- and three-photon anti-Stokes upconversion PL bands are higher than or comparable to that of the Stokes emission under excitation with low power density in the range 5-120 W/cm(2). The quantum yield of the upconversion PL was measured to be as high as ∼1.2 ± 0.1%, which is almost 4 times higher than the highest upconversion PL ...[more]

PMID: 21557587

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