Phonon-Mediated Temperature Dependence of Er3+ Optical Transitions in Single-Crystal Er2O3
Dodson, Adam
0009-0005-0843-0800
:
2024-03-25
Abstract
Rare earth ions embedded in solid state systems play a critical role in classical optical systems and have significant potential for advancing quantum information science (QIS) due to their optical emission and spin properties that resemble isolated atoms. These properties result from the intrinsic shielding of the 4f electrons due to filled out shells such as 5s and 5p. One rare earth ion, Er3+, is of particular interest because of its emission near 1.5 microns – the absorption minimum of optical fibers. The realization of potential applications requires an understanding of atomic-scale processes, including electron-phonon interactions, which are often studied through their temperature dependence. Here we present measurements and modeling of the temperature dependent photoluminescence of the 4S3/2 → 4I15/2 , 4S3/2 → 4I13/2 and 2H11/2 → 4I15/2 transition manifolds on Er3+ in Er2O3. These measurements, reported for the first time, establish a baseline for the temperature dependent behavior of the photoluminescence of Er3+ in single-crystal Er2O3 between 4 K and 300 K. The modeling of these measurements advances existing theory of the temperature dependence of rare earth ion photoluminescence and shows the need to consider the individual Stark-split levels of Er3+, their thermalization and numerous single-phonon assisted transitions utilizing the phonon modes specific to Er2O3 to explain our observations. Through this model we demonstrate differences in the electron-phonon coupling of the 4S3/2 and 2H11/2 states of Er3+ in Er2O3 and suggest that the temperature dependence of Er3+ emission intensity may vary significantly with small shifts in excitation wavelength (~0.1 nm).