1 research outputs found
Plasmonicâenhanced NIRâII downconversion fluorescence beyond 1500 nm from coreâshellâshell lanthanide nanoparticles
This paper reports on the light amplification of NaGdF4:Yb,Er,Ce@NaGdF4:Yb,Nd@NaGdF4 coreâshellâshell downconversion nanoparticles (CSSâDCNPs) in the nearâinfrared second biological window (NIRâII: 1000â1700 nm) by plasmonic nanostructures. Through a precisely controlled plasmonic metallic nanostructure, fluorescence from Yb3+ induced 1000 nm emission, Nd3+ induced 1060 nm emission, and Er3+ induced 1527 nm emission are enhanced 1.6âfold, 1.7âfold, and 2.2âfold, respectively, under an 808 nm laser excitation for the CSSâDCNPs coupled with a gold holeâcap nanoarray (AuâHCNA), while the Er3+ induced 1527 nm emission under a 980 nm laser excitation is enhanced up to 6âfold. To gain insight into the enhancement mechanism, the plasmonic modulation of Er3+ induced NIRâII emission at 1550 nm under 980 nm excitation is studied by FDTD simulation and lifetime measurements, showing the observed fluorescence enhancement can be attributed to a combination of enhanced excitation and an increased radiative decay rate