DNA-directed nanometer-scale integration of single colloidal quantum emitters with on-chip photonics

Topography-modulated DNA origami placement positions sub-10 nm colloidal quantum rods with nanometer-scale precision on lithographically defined photonic chips, enabling cavity-coupled single-photon emission.

• Why it matters: Integrated photonics needs individual colloidal quantum emitters placed with nanometer-scale accuracy, but transferring sub-10 nm particles onto micron-scale structures with high precision is difficult.
• What they did: The method patterns DNA origami templates into shape-matched resist wells on photonic chips, then uses soft-silicification-passivation to stabilize origamis while preserving DNA binding sites for selective rod attachment and polarization alignment.
• The result: The placed quantum rods show room-temperature single-photon emission, and when integrated with waveguides, micro-ring resonators, and bullseye microcavities, they achieve cavity-coupled single-photon emission.