Deterministic printing and heterointegration of single colloidal quantum dot photon sources

Single nanoparticles are essential building blocks for next-generation quantum photonic technologies, however, scalable and deterministic heterointegration strategies have remained largely out of reach. Here, we present a new electrohydrodynamic (EHD) printing model that exploits nanoscale dielectrophoretics to precisely print single colloidal quantum dots (QDs) with accuracies allowing for fully-additive nanoscale photonics integration. Using colossal-shelled QDs solubilized in apolar solvents, this method overcomes continuum fluid surface energetics and stochastic limitations, achieving selective extraction and deposition of individual QDs at sub-zeptoliter volumes. Photoluminescence and autocorrelation function (g(2)) measurements confirm nanophotonic cavity-QD integration and the first single-photon emission from printed QDs. This additive, zero-waste nanomanufacturing process offers a scalable, sustainable pathway for heterointegrating nanomaterials down to the single particle level.