1. Excitons and traps in rare-earth materials probed by a free-electron laser Michael F Reid Jon Wells, Pubudu Senanayake Alex Salkeld, Roger Reeves Giel Berden, FELIX Andries Meijerink, Utrecht Chang-Kui Duan, USTC, China NZIP, Wellington, October 18, 2011
14. SrCl 2 :Yb 2+ : Sánchez-Sanz et al. J. Chem. Phys. 133, 114509 (2010) Yb 2+ Cl - /F - Sr 2+ /Ca 2+ Sr Cl 2 : Yb 2+ / Ca F 2 : Yb 2+
15. SrCl 2 :Yb 2+ 4f 14 4f 13 5d (mixed) 4f 13 6s Sánchez-Sanz et al. J. Chem. Phys. 133, 114509 2010 bond length 4f 13 5d (E) 30000 cm -1 Exciton state forms as excited electron becomes delocalized and bonds shorten
34. Trap Liberation in SrF 2 :Yb 2+ Effective even after exciton decay UV IR Exciton ESA + Trap Liberation Only Trap Liberation 200μs 400μs 600μs 800μs
35.
Editor's Notes
E state has shorter bond length than ground state. T2 longer. Can tell from pressure experiments, etc.
UV laser at left goes through wall. Felix is synchronized with the UV laser UV 1kHz, Felix 10Hz macropulses.
With ratio we get spectrum. High-energy from january with caf2 windows. I cut it off at 10microns, where it starts to dip. Medium with PbS windows Low with polypropolene windows and different FEL. Medium energy range is probably saturated.
Cubic, so MD allowed (or vibronic). The calculation is oscillator strength. The normalization of the excitation spectrum has not been worked out yet.
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