Observation of a magnetic-field-induced resonance in the homogeneous dephasing time for the 1D2-3H4 transition in Pr3+:YAlO3.

Abstract

Using two-pulse photon echo excitation a strong resonance in the measured homogeneous dephasing time as a function of magnetic field is observed in the $^{3}$${\mathit{H}}_{4}$${\mathrm{\ensuremath{-}}}^{1}$${\mathit{D}}_{2}$ transition of ${\mathrm{Pr}}^{3+}$:${\mathrm{YAlO}}_{3}$. The resonance could only be observed at low excitation energies since it otherwise was masked by excitation intensity dependent extra dephasing processes in the crystal. Thus intensity dependent dephasing processes may not only affect the apparent dephasing time of a system but may also mask other more subtle interactions in the materials studied. It is reasonable to assume that the type of resonance observed could be caused by Zeeman induced level crossings in the active ion or in the host crystal ions or, possibly, that it could be due to coincidences between Zeeman level transition frequencies. However, based on current data of the Pr:${\mathrm{YAlO}}_{3}$ system the observed resonance could not be unambiguously tied to such effects. \textcopyright{} 1996 The American Physical Society.