A device once big enough to fill an optical table has been shrunk to the size of a coin. The result brings high-precision lasers within reach of ordinary clinics, field labs and consumer gadgets.
For more than two decades, scientists chasing powerful ultrafast lasers on a tiny chip hit a hard wall. A femtosecond laser — one that fires flashes lasting just a quadrillionth of a second — has been the backbone of cutting-edge microscopy, quantum optics and precision machining. But producing those bursts required mirrors, lenses and crystals arranged across a room-sized table.
That changed when a team at the Swiss Federal Institute of Technology in Lausanne (EPFL), led by Professor Tobias J. Kippenberg, reported the first integrated ultrafast laser that matches the performance of the bulky tabletop machines it replaces. The paper appeared in the journal Nature.
EPFL’s photonic chip routes light through microscopic waveguides instead of clunky optical hardware, producing pulses as short as 147 femtoseconds and carrying up to 1.05 nanojoules of energy per pulse — a benchmark figure that matters because it marks the energy threshold where these lasers become genuinely useful.
Miniaturising this technology reshapes what ultrafast optics can do:
The breakthrough does not mean every smartphone will ship with a laser anytime soon. Engineering challenges remain — stability, heat management and yield at scale still need work. But the core physics barrier, long called the “holy grail” of integrated photonics, has finally fallen.
What once demanded a specialised optical table now fits on a millimetre-scale chip. That compression is exactly the kind of step that turns a research curiosity into a platform technology, quietly working inside the devices of tomorrow.