Observation of enhanced two-photon absorption in ZnS quantum dots at an ultraviolet wavelength

• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2011,（11）
• 页码范围: 63-66
• 页数: 4页
• 语种: 英文
• DOI: 10.3788/COL201109.101902

摘要

Two-photon absorption (2PA) in zinc sulphide (ZnS) and Mn2+-doped ZnS quantum dots is reported by the z-scan technique,with nanosecond pulsed laser radiation at 355 nm.The observed values of the 2PA cross section of all the samples are 105 times larger than that of bulk ZnS.Researchers have recently expanded their research interests to find highly potential multiphoton active materials[1-10].Amongst others,zinc sulphide (ZnS)and Mn2+-doped ZnS (ZnS:Mn) quantum dots (QDs)have been found to be potential materials because of their visible luminescence and interesting nonlinear optical (NLO) properties[5-8,10-12].Reports on the multiphoton absorption properties of ZnS QDs have been published previously.For example,two-photon absorption (2PA) has been reported by Zheng et al.with picosecond laser radiation at 532 nm in 0.5％ Mn2+-doped ZnS QDs[7].Some enhancements in 2PA have been reported in ZnSe/ZnS core/shell at 806 nm and in ZnS quantum structures at 532-nm laser pulses[13,14].