Successive excited-state absorption through a multistep process in highly Er(3+) -doped fiber pumped by a 1.48-microm laser diode.
The fluorescence spectra ranging from 400 to 1000 nm were investigated on highly Er(3+) -doped fiber pumped by a 1.48-microm laser diode. A strong green emission was observed. An investigation of the fluorescence intensity dependence on pump power revealed that the green emission is attributed to successive excited-state absorption through a three-step process and also that saturation of the atomic levels that contribute to the emission occurs.
Arahira
S
S
Watanabe
K
K
Shinozaki
K
K
Ogawa
Y
Y