Resonant Fluorescence Line Narrowing in La1−xP5O14:Ndx3+

Abstract

Donor-donor and donor-acceptor dynamics in ${\mathrm{La}}_{1-x}{\mathrm{P}}_5{\mathrm{O}}_{14}:{{\mathrm{Nd}}_x}^{3+}$ are measured directly with a high-resolution, near-ir laser system. Time-resolved fluorescence line-narrowing measurements show an absence of rapid donor-donor transfer below 20 K and an onset of spectral diffusion at ≈ 20 K for an $x=0.75\mathrm{}$ sample. The linear concentration quenching and exponential decay in the absence of fast diffusion are explained with existing energy-transfer theories and are consistent with room-temperature studies.