Investigation of three-pulse photon echo in thick crystal using finite-difference time-domain method

Abstract

This paper investigates the phenomenon of three-pulse photon echo in thick rare-earth ions doped crystal whose thickness is far larger than 0.002 cm which is adopted in previous works. The influence of thickness on the three-pulse photon echo's amplitude and efficiency is analyzed with the Maxwell-Bloch equations solved by finite-difference timedomain method. We demonstrate that the amplitude of three-pulse echo will increase with the increasing of thickness and the optimum thickness to generate three-pulse photon echo is 0.3 cm for Tm 3+ :YAG when the attenuation of the input pulse is taken into account. Meanwhile, we find the expression 0.09 exp (α ′ L), which is previously employed to describe the relationship between echo's efficiency and thickness, should be modified as 1.3 • 0.09 exp (2.4 • α ′ L) with the propagation of echo considered.