EPFL Shrinks a Tabletop-Grade Ultrafast Laser Onto a Chip, Cracking a 20-Year 'Holy Grail' of Integrated Photonics

Overview

A team at the Swiss Federal Institute of Technology Lausanne (EPFL) has built the first integrated ultrafast laser capable of matching the performance of traditional tabletop femtosecond lasers, according to ScienceDaily. Writing in Nature, the researchers report a chip-scale device that delivers 1.05 nanojoules in pulses as short as 147 femtoseconds, as described by EPFL. The work was published on 3 June 2026, per Phys.org.

Ultrafast lasers — sources that emit pulses lasting only a few hundred femtoseconds — underpin precision manufacturing, eye surgery, optical frequency combs and the optical atomic clocks that keep the world’s most precise time, according to EPFL. Until now those capabilities have generally depended on bulky, expensive laboratory instruments. The EPFL result moves that performance onto a single photonic chip.

What We Know

The device is built on an erbium-doped silicon nitride chip, as reported by optics.org. Its laser cavity measures 42 centimeters in length, yet it can be folded onto a chip occupying roughly the area of a match head, according to ScienceDaily.

Rather than adapt one of the laser architectures common in integrated photonics, the team turned to the Mamyshev oscillator, a design that had received relatively little attention in the field, according to ScienceDaily. In this approach, a nonlinear waveguide sits between two optical filters that each let through a different slice of the color spectrum, as described by EPFL.

The team is led by Professor Tobias J. Kippenberg at EPFL, with Zheru Qiu as a co-leading author of the paper, according to EPFL. “This design is especially attractive because it does not require any component that is difficult to make on this erbium-doped silicon nitride chip,” Qiu said, as reported by Phys.org.

The chip reaches kilowatt-level peak power, according to Phys.org. “With kilowatt-level peak power, the chip can drive demanding applications that have long depended on large, expensive laboratory lasers,” Qiu said, as reported by Phys.org.

Because the laser is fabricated using established silicon nitride processing, more than 1,000 laser cavities could be produced at once on a single wafer, according to optics.org.

Why It Matters

For more than twenty years, a high-pulse-energy femtosecond laser on chip was widely regarded as a holy grail of integrated photonics, according to ScienceDaily. “For more than twenty years, a high-pulse-energy femtosecond laser on chip was widely regarded as a holy grail of integrated photonics,” Kippenberg said, as reported by Phys.org.

The practical appeal is in shrinking instruments that today fill an optical table. EPFL points to a range of applications the chip could eventually serve, including detecting pollutants, revealing hidden defects in materials and performing medical diagnostics, according to EPFL. The same pulses can seed optical frequency combs, the technology behind today’s most precise optical atomic clocks, also according to EPFL.

What We Don’t Know

The published work is a laboratory demonstration, and the sources do not detail manufacturing yield, long-term stability, or a timeline for commercial deployment. The wafer-scale figure of more than 1,000 cavities reflects fabrication potential rather than a shipping product, according to optics.org. How the on-chip device compares with tabletop systems across the full range of demanding applications — and at what cost — remains to be established beyond the performance figures reported in Nature.

Analysis

The significance of the EPFL result is less about a single record number and more about closing a long-standing gap between what integrated photonics promised and what it could deliver. Chip-scale lasers have existed for years, but combining short pulse duration with the pulse energy and peak power that real-world applications demand has been the persistent obstacle, which is why the field framed it as a holy grail, according to ScienceDaily. By reaching for the comparatively overlooked Mamyshev oscillator and matching it to an erbium-doped silicon nitride platform that needs no hard-to-fabricate components, the team sidestepped the parts of the problem that had stalled earlier attempts, as Qiu’s comments to Phys.org suggest. If the wafer-scale fabrication holds up outside the lab, the path from bespoke laboratory instrument to mass-produced component is what would make tools such as compact optical atomic clocks and portable diagnostics broadly accessible, according to optics.org.