多波长飞秒激光激发下GaAs纳米线SHG特性研究  

Optical SHG properties of GaAs nanowires irradiated with multi-wavelength femto-second laser pulses

作　　者：张晓青[1] 贺号[1] 胡明列[1] 颜鑫[2] 张霞[2] 任晓敏[2] 王清月[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院,光电信息技术科学教育部重点实验室,天津300072 [2]北京邮电大学信息光子学与光通信国家重点实验室,北京100876

出　　处：《物理学报》2013年第7期296-304,共9页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2010CB327600;2011CB808101);教育部博士点新教师基金(批准号:20110032120057);国家自然科学基金(批准号:61108080;61020106007)资助的课题~~

摘　　要：本文基于有限元法研究了直立生长于GaAs衬底的GaAs纳米线的光场响应和光场增强性质.实验使用多个波长的飞秒激光脉冲激发GaAs纳米线,测得了较高效率的二次谐波信号,并首次使用宽带超连续飞秒脉冲(1000—1300nm)在纳米线上获取了宽带、无杂散荧光噪声的二次谐波信号.这种高效的二次谐波产生过程主要归因于纳米结构引起的局域场增强效应.本文阐明了GaAs纳米线的二次谐波倍频特性,这些结果对于其在纳米光学中的光器件、光集成等领域的进一步研究和实际应用具有很好的参考价值.The nonlinear optical properties of semiconductor nanowires are of vital importance in the researches of nano-optics and fabrication of nano-scale optoelectronic components. GaAs is a direct bandgap semiconductor material of wide bandgap, high electron mobility, large χ（2）, high laser damage threshold and stable chemical properties, all of which make it a potential nonlinear optical material. In this report, based on the finite element method （FEM）, we investigated the optical response and local field enhancement of GaAs nanowires perpendicular to the GaAs substrate surface. Under the radiation of femto-second laser pulses at different wavelengths, efficient second harmonic generation （SHG） signal was acquired from the nanowires. Furthermore, noise-free broadband SHG signal was also detected to be excitated by super-continuous femto-second pulses （1000-1300 nm）. The high-efficiency SHG process could be attribated mainly to the local field enhancement effect of the nanowires. Our investigation is the first, as far as we know, demonstrate the SHG properties of GaAs nanowires, and the results suggest that GaAs nanowires are promising in the potential applications in nano-scale optical devices, integrated nanophotonic circuits, from which related nano-optics researches can benefit.

关 键 词：GaAs纳米线 二次谐波 飞秒激光 

分 类 号：TN304[电子电信—物理电子学] TB383.1[一般工业技术—材料科学与工程]