Oct 29, 2025

New vertical method reshapes how ultra-thin optical fibers are made

A vertical drawing system lets researchers craft ultra-thin optical fibers with nanometer precision, enabling advances in quantum tech, sensors, and lasers.

(Nanowerk News) Researchers have unveiled a new way to make ultra-thin optical fibers with extraordinary precision, a step that could speed up progress in photonics, quantum technology, and advanced sensing (Frontiers of Optoelectronics, "Precision vertical drawing of diameter-gradient microfibers: cascaded geometries for tailored nonlinearity").

Micro/nano optical fibers—so thin their diameter matches the wavelength of light—are vital for technologies such as biomedical sensors, high-speed communication, and powerful lasers. Until now, fabricating these fibers with intricate, multi-section structures has been nearly impossible. Conventional horizontal methods often suffer from turbulent heat flow, which distorts the fiber and limits design complexity.

The research team tackled that problem by flipping the process on its head—literally. They built a compact vertical drawing system that aligns the flow of hot air with gravity. “This alignment stabilizes the temperature field and gives us precise control over the fiber’s diameter along its entire length,” said the study’s lead researcher. The result is an ability to “program” each fiber’s shape down to the nanometer.

A four-segment micro/nano optical fiber with varying diameters designed to control light behavior and generate a broad, stable supercontinuum spectrum. (Image: Frontiers of Optoelectronics)

Using this setup, the group created four-segment fibers stretching 120 millimeters long, with the thinnest point just one micron wide. These carefully graded structures make it possible to manipulate light with new levels of accuracy. The fibers were optimized for a phenomenon called supercontinuum generation, which produces a broad, flat spectrum of light. Tests confirmed a stable supercontinuum range between 1463 and 1741 nanometers, achieving high efficiency and strong performance for potential use in imaging, spectroscopy, and telecom systems.

Beyond this demonstration, the vertical technique offers a new path for designing fibers with customized optical behavior. It could lead to breakthroughs in quantum light sources, precision sensors, and compact photonic circuits. Rather than improving on existing fiber methods, this approach reimagines them—paving the way for the next generation of light-based technologies.

Source: Frontiers Journals (Note: Content may be edited for style and length)