Optical ezcitation of trapped electrons in high density polyethylene (HDPE) studied through positron annihilation

摘要：

Positronium (Ps) formation in high-density polyethylene (HDPE) has been studied at temperatures below the glass transition temperature. The probability of forming Ps from an injected positron increases with positron irradiation up to some saturated value as a result of the delayed formation process. In this process the positron interacts with a trapped electron left behind from a previous positron track to form Ps. The optical de-trapping of the localized electrons has been studied by shining light of different energies into the HDPE and through the observed reduction of the saturated Ps level. The optical cross-section for electron de-trapping has been determined and is found to be constant at～10-20cm-2 in the visible and increasing into the infrared.

作者: F.Nahid J.D.Zhang T.F.Yu S.Fung C.D.Beling

作者单位: Department of Physics,The University of Hong Kong,Pokfulam Road,Hong Kong,P.R.China

会议类型: 国际会议

会议名称: 第九届国际正电子与正电子素国际会议(9th International Workshop on Positron and Positronium Chemistry)(PPC–9)

会议地点: 武汉

会议语种:英文

页码: 13

在线出版日期: 2008-05-11（万方平台首次上网日期，不代表论文的发表时间）