Assembly of Photonic Crystal Nanolasers with High-Aspect-Ratio Nanoslots via Mechanically Guided Transfer Printing

We propose and demonstrate a novel mechanically guided transfer printing technique for manufacturing a III–V two-dimensional photonic crystal (PhC) slotted nanocavity laser on a SiO₂substrate. By precisely assembling two identical PhC slabs, we form nanoslots with a width as narrow as 20 nm and an aspect ratio of approximately 12 within the PhC nanocavities. Statistical analysis shows that over 70% of the assembled nanocavities exhibit lateral lattice shifts of less than 50 nm, ensuring the accuracy and reliability of assembling the nanocavity using the proposed mechanically guided transfer printing process. In addition to identifying low-threshold lasing actions of the nanoslot modes in this III–V/SiO₂hybrid nanocavity, we also investigate the influence of lateral lattice shifts during assembly on the nanoslot mode lasing through simulations and experiments. This method offers a straightforward approach to assembling extremely narrow nanoslots between heterogeneous materials without the meticulous control required for manufacturing nanoslots using traditional scalable processes. Given the broad applicability of transfer printing to various materials, we believe this method is not limited to the demonstrations presented in this report but can also be utilized for assembling various structures featuring ultranarrow nanoslots based on heterogeneous materials in silicon-based photonic integrated circuits.