Chen Bigeng, Meng Chao, Yang Zongyin, Li Wei, Lin Shisheng, Gu Tingyi, Guo Xin, Wang Delong, Yu Shaoliang, Wong Chee Wei, Tong Limin
Opt Express. 2014 Oct 6;22(20):24276-85. doi: 10.1364/OE.22.024276.
We report the fabrication and characterization of freestanding graphene coated ZnO nanowires (GZNs) for optical waveguiding. The GZNs are fabricated using a tape-assist transfer under micromanipulation. Owing to the deep-subwavelength diameter and high index contrast of the ZnO nanowire waveguide, light-graphene interaction is significantly enhanced by the strong surface optical fields, resulting in a linear absorption as high as 0.11 dB/µm in a 606-nm-diameter GZN at 1550-nm wavelength. Launched by 1550-nm-wavelength femto-second pulses, a 475-nm-diameter GZN with a graphene coating length of merely 24 µm exhibits evident nonlinear saturable absorption with a peak power threshold down to 1.3 W. In addition, we also demonstrate a transmission modulation for 1550-nm-wavelength signal with a 590-nm-diameter GZN, showing the possibility of using GZN waveguides as nanoscale bulding blocks for nanophotonic devices.
我们报道了用于光波导的独立式石墨烯包覆氧化锌纳米线（GZNs）的制备与表征。GZNs是通过微操作下的胶带辅助转移法制备的。由于氧化锌纳米线波导的深亚波长直径和高折射率对比度，强表面光场显著增强了光与石墨烯的相互作用，在1550 nm波长下，直径为606 nm的GZNs中的线性吸收高达0.11 dB/µm。由1550 nm波长的飞秒脉冲激发时，直径为475 nm、石墨烯包覆长度仅为24 µm的GZNs表现出明显的非线性饱和吸收，峰值功率阈值低至1.3 W。此外，我们还展示了直径为590 nm的GZNs对1550 nm波长信号的传输调制，表明了使用GZNs波导作为纳米光子器件的纳米级构建块的可能性。
