Optical pumping

Optical pumping is when we use light to put energy into atoms. Just like when we eat food, our bodies get energy to move and do things, atoms also need energy to do things. But instead of food, atoms can be given energy from light.

Think of a ball in a hole. The ball is at the bottom of the hole, and it doesn't move on its own. But if you kick the ball, it gains energy and can roll out of the hole. Atoms are like the ball, and light is like the kick.

So, we use light to give energy to atoms, and this makes them move and do things. We can use this to understand and control how atoms behave, which can help us make things like lasers and other cool stuff.