Kohärenzdauern

Kohärenzdauern, also known as coherence times, are a fundamental concept in physics, particularly in the study of waves and quantum mechanics. In simple terms, a coherence time quantifies the duration over which a wave or a quantum system remains in a coherent state. Coherence refers to the synchronized behavior of the wave's oscillations or the quantum states of a system.

For light waves, a longer coherence time means the light is more monochromatic and can maintain its phase relationship over a greater distance or time. This is crucial for applications like interferometry, where precise measurements rely on the interference of light waves. Lasers, known for their high coherence, exhibit long coherence times. Conversely, light sources like incandescent bulbs have very short coherence times.

In quantum mechanics, coherence time is related to the lifespan of a quantum superposition. A quantum system in superposition exists in multiple states simultaneously. The coherence time is the period during which this superposition is maintained before decoherence occurs, causing the system to collapse into a single classical state. Maintaining long coherence times is a major challenge in developing quantum computers and other quantum technologies. Factors like environmental noise and interactions can lead to rapid decoherence and thus shorten the coherence time.