Department of Optics and Optical Engineering, Anhui Key Laboratory of Optoelectronic Science and Technology, University of Science and Technology of China , Hefei, Anhui 230026, China.
Nano Lett. 2015 Feb 11;15(2):1382-7. doi: 10.1021/nl504689s. Epub 2015 Jan 29.
Plasmonic nanolasers have ultrahigh lasing thresholds, especially those devices for which all three dimensions are truly subwavelength. Because of a momentum mismatch between the propagating light and localized optical field of the subwavelength nanocavity, poor optical pumping efficiency is another important reason for the ultrahigh threshold but is normally always ignored. On the basis of a cavity-embedded nanoantenna array design, we demonstrate a room-temperature low-threshold plasmonic nanolaser that is robust, reproducible, and easy-to-fabricate using chemical-template lithography. The mode volume of the device is ∼0.22(λ/2n)(3) (here, λ is resonant wavelength and n is the refractive index), and the experimental lasing threshold produced is ∼2.70MW/mm(2). The lasing polarization and the function of nanoantenna array are investigated in detail. Our work provides a new strategy to achieve room-temperature low-threshold plasmonic nanolasers of interest in applications to biological sensoring and information technology.
等离子体纳米激光器具有超高的激光阈值，特别是对于那些所有三个维度都真正处于亚波长的器件。由于传播光和亚波长纳米腔的局域光场之间的动量失配，光泵浦效率差是另一个重要的超高阈值原因，但通常总是被忽略。基于腔嵌入式纳米天线阵列设计，我们展示了一种室温低阈值等离子体纳米激光器，该激光器具有稳健、可重复和易于使用化学模板光刻制造的特点。该器件的模式体积约为 0.22(λ/2n)(3)（这里，λ 是共振波长，n 是折射率），实验产生的激光阈值约为 2.70MW/mm(2)。详细研究了激光的偏振和纳米天线阵列的功能。我们的工作为实现室温低阈值等离子体纳米激光器提供了一种新策略，这种激光器在生物传感和信息技术应用中具有重要意义。
