At a Glance
- Researchers in Singapore have created 3D-printed glass nanostructures that achieve nearly 100% reflectance, challenging long-held assumptions about the optical capabilities of low-index materials, such as glass.
- The team developed a novel hybrid resin called Glass-Nano, which combines silicon-bearing molecules and organic compounds to enable the printing of exceptionally smooth and detailed nanoscale structures.
- Using a precise laser printing method followed by heating to 650 degrees Celsius, the resin-based structures uniformly shrink into pure, durable silica glass while perfectly preserving their complex forms.
- Scientists fabricated highly uniform, diamond-like photonic crystals that function as perfect mirrors for visible light, with measured performance aligning excellently with theoretical predictions for idealized structures.
- This groundbreaking method could lead to advanced technologies, such as energy-efficient displays and compact sensors, paving the way for more efficient and powerful next-generation optical components.
Researchers have developed a groundbreaking method to 3D-print glass structures at the nanoscale, achieving a level of light reflection previously thought impossible for the material. A team from the Singapore University of Technology and Design (SUTD) has created intricate glass lattices that reflect nearly 100 percent of visible light. This breakthrough, published in Science Advances, challenges long-held assumptions in optics and opens the door for glass to be used in advanced applications such as high-efficiency wearable displays, compact sensors, and other devices in the field of nanophotonics, which involves controlling light on a scale smaller than its wavelength.
The team’s success hinges on a newly developed material called Glass-Nano, a hybrid resin that combines silicon-based molecules with light-sensitive organic compounds. The process begins with two-photon lithography, a highly precise 3D printing technique that uses a focused laser to solidify the liquid resin into a desired pattern. Afterward, the printed structure undergoes a heating process known as sintering at 650 degrees Celsius. This step burns away the organic components and fuses the remaining silicon elements into pure, smooth silica glass. As the structure heats up, it shrinks uniformly, resulting in features as small as 260 nanometers while perfectly preserving its complex shape. “Instead of starting with silica particles, we worked with silicon-bearing molecules in the resin formulation,” explained Professor Joel Yang, the project’s lead researcher, in a university press release. “This resin enables us to build up nanostructures with much finer detail and smoother surfaces than was previously possible.”
Using this method, the researchers fabricated photonic crystals, which are materials engineered with a repeating internal structure designed to manipulate light waves. By printing a precise, diamond-like lattice more than 20 layers thick, they created a structure that acts like a perfect mirror for visible light. This result was particularly noteworthy because glass has a low refractive index—a measure of how much a material bends light—and such materials were not expected to produce such high reflectance. “The result was unexpected,” shared Dr. Wang Zhang, a research fellow at SUTD and the study’s first author. “Historically, low-index materials like silica were seen as optically weak for this purpose. [However,] our findings show that with enough uniformity and structural control, they can outperform expectations.” The team’s experimental measurements also showed excellent agreement with computer simulations of an ideal photonic crystal, confirming the exceptional quality of the fabricated structures.
The implications of this work extend beyond creating better mirrors. The vibrant, pigment-free colors produced by these photonic crystals, known as structural color, could be used to create durable, low-power displays. Because the fabrication method is compatible with existing nanoprinting technology, these glass components could be integrated directly into a variety of devices. Looking ahead, the SUTD team is exploring ways to add new functionalities to the Glass-Nano resin, such as light emission, and developing methods for faster, large-scale production. “With the ability to print high-resolution nanostructures in both low- and high-index dielectrics, [we are] now turning to applications where 3D optical components could reduce transmission losses and enable more efficient photonic systems,” said Yang.
References
- Singapore University of Technology & Design. (2025, June 23). Glass nanostructures reflect nearly all visible light, challenging photonics assumptions. Phys.Org; Singapore University of Technology & Design. https://phys.org/news/2025-06-glass-nanostructures-visible-photonics-assumptions.html
- Zhang, W., Wang, H., Wang, H., Ha, S. T., Chen, L., Li, X. L., Pan, C.-F., Wu, B., Rahman, Md. A., Ke, Y., Ruan, Q., Yang, X., Christensen, T., & Yang, J. K. W. (2025). Nanoscale 3D printing of glass photonic crystals with near-unity reflectance in the visible spectrum. Science Advances, 11(21), eadv0267. https://doi.org/10.1126/sciadv.adv0267
