Three‐dimensional (3D) subwavelength nanostructures have emerged and triggered tremendous excitement because of their advantages over the two‐dimensional (2D) counterparts in fields of plasmonics, photonic crystals, and metamaterials. However, the fabrication and integration of 3D nanophotonic structures with colloidal quantum dots (CQDs) faces several technological obstacles, as conventional lithographic and etching techniques may affect the surface chemistry of colloidal nanomaterials. Here, the direct fabrication of functional quasi‐3D nanophotonic structures into CQD films is demonstrated by one‐step imprinting with well‐controlled precision in both vertical and lateral directions. To showcase the potential of this technique, diffraction gratings, bilayer wire‐grid polarizers, and resonant metal mesh long‐pass filters are imprinted on CQD films without degrading the optical and electrical properties of CQD. Furthermore, a dual‐diode CQD detector into an unprecedented mid‐wave infrared two‐channel polarization detector is functionalized by embedding an imprinted bilayer wire‐grid polarizer within the CQDs. The results show that this approach offers a feasible pathway to combine quasi‐3D nanostructures with colloidal materials‐based optoelectronics and access a new level of light manipulation.
Constructing colloidal particles into functional nanostructures, materials, and devices is a promising yet challenging direction. Many optical techniques have been developed to trap, manipulate, assemble, and print colloidal particles from aqueous solutions into desired configurations on solid substrates. However, these techniques operated in liquid environments generally suffer from pattern collapses, Brownian motion, and challenges that come with reconfigurable assembly. Here, we develop an all-optical technique, termed optothermally-gated photon nudging (OPN), for the versatile manipulation and dynamic patterning of a variety of colloidal particles on a solid substrate at nanoscale accuracy. OPN takes advantage of a thin surfactant layer to optothermally modulate the particle-substrate interaction, which enables the manipulation of colloidal particles on solid substrates with optical scattering force. Along with in situ optical spectroscopy, our non-invasive and contactless nanomanipulation technique will find various applications in nanofabrication, nanophotonics, nanoelectronics, and colloidal sciences.
more » « less- Award ID(s):
- 1761743
- NSF-PAR ID:
- 10154262
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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