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arXiv · 1709.01997

Electron spin dynamics of Ce$^{3+}$ ions in YAG crystals studied by pulse-EPR and pump-probe Faraday rotation

D. V. Azamat·V. V. Belykh·D. R. Yakovlev·F. Fobbe·D. H. Feng·E. Evers·L. Jastrabik·A. Dejneka·M. Bayer
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Abstract

The spin relaxation dynamics of Ce$^{3+}$ ions in heavily cerium-doped YAG crystals is studied using pulse-electron paramagnetic resonance and time-resolved pump-probe Faraday rotation. Both techniques address the 4$f$ ground state, while pump-probe Faraday rotation provides also access to the excited 5$d$ state. We measure a millisecond spin-lattice relaxation time $T_1$, a microsecond spin coherence time $T_2$ and a $\sim 10$ ns inhomogeneous spin dephasing time $T_2^*$ for the Ce$^{3+}$ ground state at low temperatures. The spin-lattice relaxation of Ce$^{3+}$ ions is due to modified Raman processes involving the optical phonon mode at 125 cm$^{-1}$. The relaxation at higher temperature goes through a first excited level of the $^{2}$F$_{5/2}$ term at about $\hbar \omega \approx 228$ cm$^{-1}$. Effects provided by the hyperfine interaction of the Ce$^{3+}$ with the $^{27}$Al nuclei are observed.

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D. V. Azamat, V. V. Belykh, D. R. Yakovlev, F. Fobbe, D. H. Feng, E. Evers, L. Jastrabik, A. Dejneka, M. Bayer. 2017-09-04. Electron spin dynamics of Ce$^{3+}$ ions in YAG crystals studied by pulse-EPR and pump-probe Faraday rotation. https://doi.org/10.1103/physrevb.96.075160

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