1.7 MU-M EXCITED-STATE ABSORPTION MEASUREMENT IN ERBIUM-DOPED GLASSES

We have measured the complete 1.7 mu m excited state absorption (ESA) spectrum in erbium-doped glasses. The spectrum is obtained by measurin g the gain of an erbium-doped waveguide in the 1400-1800 nm region. Us ing the measured spectra, we estimate the 1.5 mu m uniform upconversio n rate by calculating the spectral overlap between the 1.5 mu m emissi on and 1.7 mu m ESA cross sections. The technique is applied to erbium -doped, ion-exchangeable silicate glasses yielding upconversion consta nts in the range of 1-10x10(-18) cm(3)/s. (C) 1995 American Institute of Physics.