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A. Meijerink

Publications and source records attributed to A. Meijerink.

3 recordsLinked to original sources

Controlled emission and coupling of small-size YAG:Ce3+ nanocrystals to gold nanowire

We report a controlled emission of Ce3+ ions inside single Yttrium Aluminum Gar- net Y3Al5O12 (YAG:Ce3+) nanocrystals with a diameter of 22 +- 10 nm as a result of a coupling of a surface plasmon mode propagating along single gold nanowire (NW). From the PL images, the intensity for single YAG:Ce3+ nanocrystals in the proximity of the single gold NW increases by a factor of two in comparison with that without the NW. Also, we observe a maximum of 3.8-fold emission rate en- hancements for the single nanocrystal close to the single gold NW. The emission rate enhancements of YAG:Ce3+ nanocrystals are two folds the enhancements of 100-nm fluorescent nanospheres. This value is in agreement with the calculation of a combi- nation from the analytical scattering model and boundary element method (BEM). We also confirm that the small size light sources are more efficient for the emission rate enhancements. Thus, the controlled emission of small YAG:Ce3+ nanocrystals with the perfect photostabilities will pave the way for the ultimate efficient nanoscale light sources.

physics.optics

The observation of electron trap liberation in MgF$_{2}$ doped with Yb$^{2+}$ using a two-color excitation experiment

We utilize the optical transitions of Yb$^{2+}$ excited by an ultraviolet optical parametric amplifier to probe electron trap liberation in MgF$_{2}$ via the observation of a photoluminescence enhancement effect induced by a subsequent infrared pulse from a free-electron laser. The temperature dependence of the enhancement suggests that we liberate very shallow traps having a depth of approximately 17 cm$^{-1}$. The observed `trap spectrum' is consistent with a simple model of a Coulomb trap.

cond-mat.mtrl-sci