Dźwięki wydawane przez walenie bardzo przypominają ludzkie głosy. Od wieków więc nas fascynują. Do dziś jednak niewiele na ten temat wiadomo. Citizen Science Alliance stworzyło więc społecznościowy projekt naukowy na platformie Zooniverse.org - The Whale Song Project, czyli Śpiew wielorybów. Po przeczytaniu krótkiego samouczka każdy może pomóc naukowcom lepiej zrozumieć zachowania tych zwierząt.

We demonstrated two methods of increasing the bandwidth of a broadband light source based on amplified spontaneous emission in thulium-doped fibres. Firstly, we have shown by means of a comprehensive numerical model that the full-width at half maximum of the thulium-doped fibre based broadband source can be more than doubled by using specially tailored spectral filter placed in front of the mirror in a double-pass configuration of the amplified spontaneous emission source. The broadening can be achieved with only a small expense of the output power. Secondly, we report results of the experimental thulium-doped fibre broadband source, including fibre characteristics and performance of the thulium-doped fibre in a ring laser setup. The spectrum broadening was achieved by balancing the backward amplified spontaneous emission with back-reflected forward emission.