A new process called fiber nanoimprinting is accelerating the fabrication of nano-optical devices, such as this pyramid-shaped Campanile probe imprinted on an optical fiber (captured in a scanning electron microscope image). The gold layer is added after imprinting. The gap at the top is 70 nm wide. (Credit: Berkeley Lab)

Combining speed with incredible precision, a team of researchers has developed a way to print a nanoscale imaging probe onto the tip of a glass fiber as thin as a human hair, accelerating the production of the promising new device from several per month to several per day.

The high-throughput fabrication technique, called fiber nanoimprinting, opens the door for the widespread adoption of this and other nano-optical structures. Nano-optics have the potential to be used for imaging and sensing.

Scientists create a mold with the precise dimensions of the nano-optical device they want to print. The mold is filled with a special resin and then positioned atop an optical fiber. Infrared light is sent through the fiber, which enables the scientists to measure the exact alignment of the mold in relation to the fiber. UV light is sent through the fiber, which hardens the resin. A final metallization step coats the sides with gold layers.

The faster production pace gives researchers a batch in case one breaks. Plus it’s easier to optimize nano-optical devices if scientists are able to provide feedback on a device’s performance, and an improved batch is quickly developed for further testing. The fabrication technique can be applied to any nano-optical device.