Inhomogeneous and homogeneous linewidth are reported in a Eu
3+ doped transparent Y
2O
3 ceramic for the
7F
0-
5D
0 transition, using high-resolution coherent spectroscopy. The 8.7-GHz inhomogeneous linewidth is close to that of single crystals, as is the 59-kHz homogeneous linewidth at 3 K (
T2 = 5.4 $\ensuremath{\mu}$s). The homogeneous linewidth exhibits a temperature dependence that is typical of a crystalline environment, and additional dephasing observed in the ceramic is attributed to magnetic impurities or defects introduced during the synthesis process. The absence of Eu
3+segregation at the grain boundaries, evidenced through confocal microfluorescence, further indicates that the majority of Eu
3+ions in the ceramic experience an environment comparable to a single crystal. The obtained results suggest that ceramic materials can be competitive with single crystals for applications in quantum information and spectral hole burning devices, beyond their current applications in lasers and scintillators.
Two-pulse, stimulated and accumulated photon echoes are investigated for the first time in a highly doped crystal Tm:YAG containing 10 at.% Tm 3+ . The decay curves of the two-pulse and stimulated photon echoes generated at 793.15 nm on the transition 3 H 6 (1)– 3 H 4 (1) of the impurity ions are measured in the absence of an applied magnetic field and parameters describing the energy and phase relaxation are determined. The dependence of the intensity of the accumulated photon echo on the number of excitation pulse pairs is investigated.
We present a case study on Eu 3+ -doped Y 2 O 3 transparent ceramics in which high-resolution laser spectroscopy is used as a material characterization tool. By comparing the results from coherent and incoherent optical spectroscopy with other characterization methods, we show that optical techniques can deliver supplementary information about the local environment of the activator ions in materials. Thus, high-resolution spectroscopy may be of interest for the investigation of a wider range of rare earth doped optical materials beyond materials studied for quantum information technology. The refinement of optical spectroscopy for the study of narrow optical transitions in rare earth ion single crystals has demonstrated that these techniques are extremely sensitive tools for probing the local environment of the rare earth ion. These techniques, such as photon echo experiments, have been important in developing materials for quantum information technology and spectral filtering applications. Here, we apply these techniques to transparent ceramic samples and compare the results with information gained from conventional material characterization techniques. Our present study demonstrates the high sensitivity of laser spectroscopic methods to microstructural strain and the presence of defects. In particular, the sensitivity is sufficient to detect small changes introduced by different thermal treatments in nominally equivalent materials. The results of our work show that it is possible to relate high-resolution optical measurements to defects and microstructural strain.