Real-time tunable lasing from plasmonic nanocavity arrays

• Published in: Nature communications Vol. 6; no. 1; p. 6939
• Main Authors: Yang, Ankun, Hoang, Thang B., Dridi, Montacer, Deeb, Claire, Mikkelsen, Maiken H., Schatz, George C., Odom, Teri W.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 20-04-2015; Nature Publishing Group; Nature Pub. Group
• Subjects: 639/624/399/354; 639/766/25; 639/766/400/1021; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms7939

Plasmon lasers can support ultrasmall mode confinement and ultrafast dynamics with device feature sizes below the diffraction limit. However, most plasmon-based nanolasers rely on solid gain materials (inorganic semiconducting nanowire or organic dye in a solid matrix) that preclude the possibility of dynamic tuning. Here we report an approach to achieve real-time, tunable lattice plasmon lasing based on arrays of gold nanoparticles and liquid gain materials. Optically pumped arrays of gold nanoparticles surrounded by liquid dye molecules exhibit lasing emission that can be tuned as a function of the dielectric environment. Wavelength-dependent time-resolved experiments show distinct lifetime characteristics below and above the lasing threshold. By integrating gold nanoparticle arrays within microfluidic channels and flowing in liquid gain materials with different refractive indices, we achieve dynamic tuning of the plasmon lasing wavelength. Tunable lattice plasmon lasers offer prospects to enhance and detect weak physical and chemical processes on the nanoscale in real time.
Plasmonic lasers offer ultrasmall mode confinement via nanoscale structures, but their reliance on solid-state gain media makes tunability difficult. Yang
et al
, present a laser based on gold nanoparticle arrays in a microfluidic channel, whose liquid gain media enable dynamic tuning of the lasing wavelength.