Are random lasers really random?

Randomness may be intractable and could hamper human beings from discovering underlying rules. Yet, somehow, large amounts of randomness can bring about grand patterns in nature. Randomness truly underpins human curiosity to understand the truth. Random lasers, as one of the paradigms of disordered photonics, feature chaotic lasing behavior. Due to the absence of resonant cavities, random lasing modes resulting from multiple scattering show extreme complexity, which can neither be predicted accurately nor investigated comprehensively. In this work, we build a platform to systematically and methodically analyze random lasing profiles under the scope of big data. Our results show fixed and stable laser spikes and suggest photon localization in typical and common random laser systems without any specially designed cavities. By revealing the general rules encoded in randomness, we identify one of the most important characteristics of random laser research and propose a possible answer to the fundamental question, “Are random lasers really random?”