Improving the intensity and efficiency of compressed echo in rare-earth-ion-doped crystal

Ma Xiu-Rong^{1, 2}, Liang Yu-Qing^{1, †,}, Wang Song¹, Zhang Shuang-Gen^{1, 2}, Shan Yun-Long¹

Efficiency of 3PE as a function of rephasing pulse #3’s area for different optical thickness αL. Inset: for larger αL, the maximum efficiency is much larger than unity.