Photon-echo nuclear double resonance in LaF3:Pr3+

Using the photon-echo-nuclear-double-resonance technique, we have measured the nuclear hyperfine splittings in the excited ${}_{}{}^1{}_{}{}^{}D_2^{}{}_{}{}^{}$ state of La${\mathrm{F}}_3$:${\mathrm{Pr}}^{3+}$. Our measurements are in agreement with the results obtained by Erickson from his saturated-and-enhanced-absorption study of the ${}_{}{}^3{}_{}{}^{}H_4^{}{}_{}{}^{}-{}_{}{}^1{}_{}{}^{}D_2^{}{}_{}{}^{}$ transition in La${\mathrm{F}}_3$:${\mathrm{Pr}}^{3+}$.