Surface plasmon polariton laser based on a metallic trench Fabry-Perot resonator
Wenqi Zhu, Ting Xu, Haozhu Wang, Cheng Zhang, Parag B. Deotare, Amit K. Agrawal, Henri J. Lezec
Recent years have witnessed growing interest in the development of lasers with small footprint for their potential applications in small-volume sensing and on-chip optical communications. Surface-plasmons electromagnetic modes evanescently confined to metal-dielectric interfaces offer an effective route to achieving lasing at nanometer-scale dimensions when resonantly amplified in contact with a gain medium (1, 2). For example, optically-pumped lasing modes have been demonstrated under the form of localized surface plasmons on dye-coated resonant nanoparticles or nanoparticle arrays (3, 4), as well as propagating gap plasmons confined to a dielectric layer of nanoscale thickness between a metal surface and a semiconductor gain medium (4, 5). Here, we show, for the first time, how lasing can be achieved from surface plasmon- polaritons (SPPs) freely propagating on an open, flat metal surface coated with a subwavelength-thick layer of gain medium. This is achieved by leveraging a template-stripped, micron-scale, trough-shaped rectangular cavity structure with ultra-smooth Ag sidewalls and floor, to act as a record-high quality factor SPP resonator. By incorporating a dye-doped polymer film on the trough floor, to a thickness less than the evanescent decay length of the SPP away from the metal surface, and optically pumping the dye from the open side of the cavity, we demonstrate room-temperature SPP lasing in the red with an ultra-narrow linewidth (
, Xu, T.
, Wang, H.
, Zhang, C.
, Deotare, P.
, Agrawal, A.
and Lezec, H.
Surface plasmon polariton laser based on a metallic trench Fabry-Perot resonator, Science Advances, [online], https://doi.org/10.1126/sciadv.1700909
(Accessed December 4, 2023)