Tiny chip-based laser can sniff out chemicals
MIT researchers have built a tiny laser device—small enough to fit on a chip—that can instantly detect chemicals, even in tiny amounts.
It works by shining special infrared light and picking up each chemical's unique "fingerprint."
Because everything's packed onto one chip, it could be used for things like checking air quality or spotting leaks in factories, even from far away.
The breakthrough
Lasers usually struggle with something called dispersion, which messes up their accuracy.
The MIT team solved this by adding a double-chirped mirror right onto the chip—a tricky process that meant etching super-fine layers just nanometers apart.
Thanks to this move, their laser works reliably at room temperature and doesn't need bulky extra parts.
What's next?
This tech could lead to portable sensors that quickly find dangerous gasses or pollution wherever you are.
It might also boost other types of lasers, making them more powerful and versatile.
In the long run, we could see mass-produced sensors helping keep our environment—and workplaces—safer and cleaner.