New 'quantum distillation' method allows measuring coherence of quantum states

One of the main principles of quantum physics is the superposition of states. Systems exist simultaneously in different states until they are measured and the system opts for one of the possibilities. As long as the superposition lasts, the system is said to be in a coherent state. In real systems, sets of diverse elemental particles or atoms exist in a state of superposition, for example, in different positions simultaneously, with different levels of energy, or with two opposite spin orientati