Level 1 - Absolute Beginner
Scientists made a very small laser. It fits on a tiny chip. This is a big new discovery.
The laser is very fast. It makes short bursts of light. Scientists worked on this for 20 years.
This tiny laser can help doctors and scientists. One day it could be used in small phones or medical tools.
- laser
- a very focused and powerful beam of light
- chip
- a very small piece of electronic material
- tiny
- very small
- burst
- a short, quick release of something like light or energy
- scientist
- a person who studies how the world works through experiments
- discovery
- finding or making something new and important
- powerful
- very strong
- device
- a machine or tool made to do a job
Level 2 - Elementary
Scientists at the Swiss university EPFL have succeeded in placing a powerful ultrafast laser onto a microchip. The team was led by Professor Tobias Kippenberg. They published their results in the journal Nature in June 2026.
A femtosecond laser produces extremely short pulses of light, each lasting only a few millionths of a billionth of a second. For more than 20 years, researchers tried to shrink these lasers from large laboratory equipment to tiny chips, but none could match the performance of the full-size versions until now.
This chip-sized laser could one day be used in handheld medical devices, more accurate atomic clocks, LiDAR systems used in self-driving cars, and eye surgery tools. Professor Kippenberg called it the holy grail of integrated photonics.
- ultrafast
- moving or operating extremely quickly, far beyond normal speeds
- microchip
- a tiny electronic circuit built onto a small piece of silicon
- femtosecond
- one millionth of a billionth of a second, an extremely short period of time
- photonics
- the science of using light to perform useful functions
- integrated
- combined into a single unit so all parts work together
- LiDAR
- a technology that uses laser pulses to measure distances and create maps of surroundings
- pulse
- a short burst of light, electricity, or energy
- miniaturize
- to make something much smaller without reducing how well it works
Level 3 - Intermediate
After more than two decades of failed attempts, researchers at EPFL (Ecole Polytechnique Federale de Lausanne) in Switzerland have achieved a milestone in laser physics: the first integrated femtosecond laser capable of matching the output of bulky tabletop systems. The work, led by Professor Tobias Kippenberg and published in Nature in June 2026, delivers pulses as short as 147 femtoseconds at an energy of 1.05 nanojoules using a photonic chip roughly the size of a fingernail.
Femtosecond lasers produce pulses of light so brief that 147 of them would pass in less time than it takes light to travel the width of a human hair. Such precision enables applications that were otherwise impossible, including precision machining without heat damage, optical frequency combs used in the world's most accurate atomic clocks, and the detection of glucose levels through skin tissue without a needle.
The team's key innovation was adapting a Mamyshev oscillator architecture to the constraints of photonic integrated circuits. By confining the light inside waveguides etched onto a silicon-based chip rather than directing it through mirrors and optical fibers on a laboratory table, they eliminated the size and cost barriers that had made femtosecond technology inaccessible outside of research laboratories. Professor Kippenberg called the result the holy grail of integrated photonics, a phrase that reflects both the technical difficulty and the enormous commercial potential of the achievement.
- integrated photonics
- the technology of building miniaturized optical components onto a single chip, similar to how electronics are built on microchips
- femtosecond
- one quadrillionth of a second (10 to the minus 15 power), an almost unimaginably brief unit of time
- Mamyshev oscillator
- a type of laser design that uses spectral filtering to generate ultrashort, clean pulses of light
- waveguide
- a microscopic channel etched into a chip that confines and directs light along a precise path
- optical frequency comb
- a laser tool generating a precise spectrum of evenly spaced frequencies, used in atomic clocks and molecular sensing
- nanojoule
- a billionth of a joule, a unit measuring the tiny amount of energy in a single laser pulse
- silicon photonics
- the use of silicon as a medium for building miniaturized optical devices and circuits
- precision machining
- manufacturing techniques using tightly controlled laser energy to cut materials with minimal collateral heat damage
Level 4 - Advanced
A long-sought milestone in integrated photonics was reached in June 2026 when Professor Tobias Kippenberg's group at EPFL published in Nature the first on-chip femtosecond laser capable of rivaling tabletop Kerr-lens mode-locked titanium-sapphire and erbium-fiber master oscillators in pulse duration and energy. The device delivers 147-femtosecond pulses at 1.05 nanojoules, a combination that had proved elusive for over twenty years of photonic integration research, because pulse compression and energy storage are thermodynamically antagonistic within the geometric constraints of a silicon-nitride waveguide.
The team's enabling insight was the transplantation of the Mamyshev oscillator topology onto a chip-scale silicon-nitride photonic platform. In the Mamyshev design, two spectral-filtering stages separated by a nonlinear amplifying section generate clean, self-compressed pulses. By exploiting the anomalous group-velocity dispersion of the nitride waveguide and engineering the nonlinear coefficient through waveguide cross-section geometry, the team achieved the soliton-compression dynamics previously accessible only with bulk optics or kilometer-scale single-mode fiber spools.
The commercial implications extend across multiple verticals. In metrology, chip-scale optical frequency combs could enable GPS-independent navigation accurate to centimeters and portable redefinition of the SI second. In medicine, needle-free transcutaneous glucose monitoring, currently confined to near-infrared spectroscopy proof-of-concept labs, becomes plausible as a wearable consumer device. In automotive and aerospace LiDAR, replacing discrete-component pulsed systems with monolithic photonic chips promises a tenfold reduction in module cost and a threefold improvement in angular resolution. Professor Kippenberg, asked to characterize the work, called it the holy grail of integrated photonics, a phrase that simultaneously names the two-decade duration of the quest and its arrival at a commercially viable inflection point.
- mode-locked laser
- a laser whose output consists of a periodic train of extremely short pulses, produced by synchronizing the phases of many cavity modes
- soliton
- a stable, self-reinforcing waveform that maintains its shape as it propagates, exploited in ultrafast laser pulse compression
- anomalous group-velocity dispersion
- a condition in a waveguide where shorter optical wavelengths travel faster than longer ones, enabling pulse compression
- metrology
- the science of precision measurement and the development of measurement standards
- transcutaneous
- passing through or across the skin, used in medical contexts for non-invasive monitoring
- photonic integrated circuit
- a chip on which multiple optical components are fabricated to guide, process, and detect light, analogous to an electronic integrated circuit