We thank X.Yao,X.Han,G.Chen,W.Li,G.Wang,and Y.Zhang for fruitful discussions.The work was supported by the National Natural Science Foundation of China under Grant Nos.61525505,11774310, 61705193;by the Key Scientific and Technological Innovation Team Project in Shaanxi Province(2015KCT-06);and by China Postdoctoral Science Foundation(2017M610367).
Real-time spectroscopy based on an emerging time-stretch technique can map the spectral information of optical waves into the time domain,opening several fascinating explorations of nonlinear dynamics in mode-locked l...