Influence of improved anti-Stokes energy transfer between rare earth ions in ErP5O14 noncrystal on dynamic study

Abstract

Since the visible quantum cutting in Eu3+–Gd3+ material was reported, the importance, the application, and the significance of the quantum cutting phenomenon have been widely recognized.The rate equations which describe the luminescence dynamic processes for different concentrations of (ErxLa1-xP5O14) noncrystal are established in this paper. The coefficients exp{hc k/kT} is introduced in to the calculation of anti-Stokes energy transfer rate to distinguish Stokes energy transfer.All dynamic processes have been simulated separately with and without considering this coefficient for the energy transfer rate of Er0.01La0.99P5O14,Er0.1La0.9P5O14 and ErP5O14 noncrystals when their 2H11/2 ,4I9/2 and4I11/2 levels are excited.The results show that it is essential to take the coefficient into calculation particularly for ErP5O14 noncrystal where energy transfer plays a key role.There is no influence though the distance between rare earth ions is larger.And it is found that infrared quantum cutting exsists in ErP5O14 noncrystal excited by visible light. The relative nonradiative relaxation rate, the spontaneous emission rate and the energy transfer rate are calculated particularly , The relative energy transfer dynamics is analyzed.It is found that the {4H11/2→4I9/2,4I15/2→4I13/2} energy transfer with a rate of 239500s-1, is the main reason for 2H11/2 energy level to have the infrared quantum cutting, Which is meaningful for finding high-efficiency solar cell materials.