Near-infrared to visible upconversion in Er3+ doped Cs3Lu2Cl9, Cs3Lu2Br9, and Cs3Y2I9 excited at 1.54 µm

Share/Save/Bookmark

Lüthi, Stefan R. and Pollnau, Markus and Güdel, Hans U. and Hehlen, Markus P. (1999) Near-infrared to visible upconversion in Er3+ doped Cs3Lu2Cl9, Cs3Lu2Br9, and Cs3Y2I9 excited at 1.54 µm. Physical Review B: Condensed matter and materials physics, 60 (1). pp. 162-178. ISSN 1098-0121

[img]PDF
Restricted to UT campus only
: Request a copy
333Kb
Abstract:A detailed study of upconversion processes in Cs3Er2X9 (X = Cl, Br, I) crystals and in the diluted systems Cs3Lu2Cl9:1% Er3+, Cs3Lu2Br9:1% Er3+, and Cs3Y2I9:1% Er3+ is presented. Efficient two-, three-, and four-step upconversion excitation along the sequence 4I15/2 4I13/2 4I9/2 4S3/2 2H9/2 leading to luminescence throughout the visible and near UV is demonstrated using a 1.54-µm excitation wavelength. This stepwise excitation is possible due to the low phonon energies and, consequently, the significantly longer lifetime of the 4I9/2 intermediate state in these systems relative to oxides and fluorides. The absorption and upconversion luminescence intensities increase along the isostructural series X = Cl, Br, I as a result of the decreasing energy of the electric-dipole allowed 4f-5d transitions and, thus, their increasing influence on the parity forbidden 4f-4f transitions. The excitation mechanisms in the chloride systems are investigated by time-resolved spectroscopy and the respective dynamics is studied by a rate-equation model. In the diluted sample 4I9/2 4S3/2 excited-state absorption plays a major role and occurs within 3 cm-1 of the ground-state absorption, whereas the dynamics in the concentrated system is dominated by energy-transfer upconversion (ETU) in all excitation steps. Of the 35 most likely ETU processes, eight are found to contribute significantly to the excitation mechanisms in the concentrated system. The excitation pathways leading to red luminescence from 4F9/2 are also partly resolved.
Item Type:Article
Copyright:© 1999 American Physical Society
Faculty:
Electrical Engineering, Mathematics and Computer Science (EEMCS)
Research Group:
Link to this item:http://purl.utwente.nl/publications/70100
Official URL:http://dx.doi.org/10.1103/PhysRevB.60.162
Export this item as:BibTeX
EndNote
HTML Citation
Reference Manager

 

Repository Staff Only: item control page