How can ultrafast lasers be shrunk onto a tiny chip?

Ultrafast lasers can be shrunk onto a tiny chip by turning them into super-fast little light switches that fit on a small piece of glass.

Imagine you have a flashlight that can blink on and off billions of times every second, that’s how fast these tiny lasers work. But instead of holding the flashlight in your hand, scientists put it inside a chip, which is like a mini robot made of glass and metal that fits in your palm.

Scientists use special materials that behave like light highways. When you send electric signals through them, they make the light blink super fast, just like when you flick a switch on and off really quickly.

These tiny lasers are so small, you could line up millions of them across a fingernail. They're built using layers of glass and metal that are thinner than a hair. Scientists use tools to carve these layers with precision, just like how you might cut paper with scissors, but much, much smaller.

By putting all these little light switches on one chip, scientists make devices that can do amazing things, like zapping tiny parts in computers or helping doctors see inside the body!