Coherent states

Coherent states are a special kind of quantum state where all of the particles of a system are in the same kind of state. This means that all the particles in this state have the same direction of their spin, called "coherence". A simple analogy would be a light bulb that has a bunch of lightbulbs inside it. If all the lightbulbs are pointing in the same direction, the light bulb will emit a strong, consistent light. The same idea applies to coherent states, where all of the particles of the system have their spin pointing in the same direction, producing a strong, consistent energy.