In:
Journal of Applied Physics, AIP Publishing, Vol. 104, No. 6 ( 2008-09-15)
Abstract:
Observed is 15 times enhancement of Ho3+ green upconversion (UC) emission in Ho3+(0.75 mol %)/Nd3+(0.75 mol %) doped lithium niobate crystal after incorporating with 4 mol % of Yb3+ under 800 nm femtosecond laser excitation. Yb3+ acting as bridging ion increases the energy transfer efficiency from Nd3+ F43/2 level to Ho3+ in these triply doped systems. The nonradiative energy transfer efficiency from Nd3+ F43/2 to Yd3+ F25/2 level can reach to 56%. The UC emission mechanisms are proposed based on spectral, kinetic, and pump power dependence analyses. The green UC emission is accomplished through a multi-ion interaction involving ground state absorption by the Nd3+ (I49/2→H29/2,F45/2) followed by three successive energy transfer processes involving one Nd3+-Yb3+ (F43/2+F27/2→I49/2+F25/2) and two Yb3+-Ho3+ pairs (F25/2+I58→F27/2+I56 and F25/2+I56→F27/2+S52,F54); whereas the red is dominated by excited state absorption of the Ho3+ (I57→F55) following two successive energy transfer processes involving the Nd3+-Yb3+ (F43/2+F27/2→I49/2+F25/2) and Yb3+-Ho3+ pairs (F25/2+I58→F27/2+I56) followed by the Ho3+ nonradiative relaxation to I57.
Type of Medium:
Online Resource
ISSN:
0021-8979
,
1089-7550
Language:
English
Publisher:
AIP Publishing
Publication Date:
2008
detail.hit.zdb_id:
220641-9
detail.hit.zdb_id:
3112-4
detail.hit.zdb_id:
1476463-5
