Two-dimensional distributed feedback lasers with thermally-nanoimprinted perylenediimide-containing films

Abstract

Two-dimensional (2D) distributed feedback (DFB) lasers with gratings imprinted by thermal nanoimprint lithography on the active film are reported. They show thresholds for lasing of ∼10 kW/cm2, similar to the most efficient imprinted DFB lasers reported; and long operational lifetimes (under ambient conditions) of ∼12 × 104 pump pulses. The key for their successful operation has been the selection of a highly efficient and stable dye, perylene orange (PDI-O), and a proper matrix to host it, the fluoro-modified thermoplastic resist mr-I7030R, which has enabled 2D imprinting while preserving the dye optical properties. The use of the UV-curable resist SU8 as an alternative matrix for PDI-O to be imprinted by combined nanoimprint and photolithography was also investigated, and was concluded to be unsuccessful due to severe photoluminescence quenching. By replacing PDI-O with Rhodamine 6G, lasers with reasonable thresholds, but with significantly inferior operational lifetimes in comparison to PDI-O/mr-I7030R devices, were obtained.