In quantum physics, some of the most interesting effects are the result of interferences. Decoherence, or loss of coherence, occurs when a quantum system eventually loses the ability to produce interferences, due to external noise or coupling to a larger and unmonitored system (i.e. the surrounding environment).
Click here for original story, Study observes anomalous decay of coherence in a dissipative many-body system
Source: Phys.org