Fabrication of relief tunable embedded micropillars for quantum light emission with 2D materials

The intense light-matter interactions in 2D materials can be tailored with stimuli such as localized strain and their atomically thin structure allows them to be precisely positioned to nanophotonic antennas that are designed to manipulate and further enhance their light-matter interactions. Embedded antenna architectures are versatile structures that present a new paradigm for nanophotonic engineering and nano-optomechanics in 2D materials, with applications spanning from on-demand single-photon emitters to high Q-factor optomechanical resonators. Here, the fabrication of metallic micropillars embedded in a SiO₂ dielectric cavity with diameters of 1-3 µm is described alongside photoluminescence, atomic force microscopy, and scanning electron microscopy characterization of WSe₂ flakes that have been transferred onto the micropillar. The proof-of-concept fabrication process demonstrates that with an appropriate SiO₂ thickness, the relief of the embedded pillars can be tuned to either rise above or below the cavity with nanoscale precision and sets the stage for deeper miniaturization of the micropillar and the cavity using thermal scanning probe lithography. This precision will prove crucial for future use of the structures as nano stressors or plasmonic nanoantennae.