Guo, XunminChen, HailongWen, XiewenZheng, Junrong2017-06-052017-06-052015Guo, Xunmin, Chen, Hailong, Wen, Xiewen, et al.. "Electron-phonon interactions in MoS2ﾠprobed with ultrafast two-dimensional visible/far-infrared spectroscopy." <i>The Journal of Chemical Physics,</i> 142, no. 21 (2015) AIP Publishing LLC.: http://dx.doi.org/10.1063/1.4921573.https://hdl.handle.net/1911/94770An ultrafast two-dimensional visible/far-IR spectroscopy based on the IR/THz air biased coherent detection method and scanning the excitation frequencies is developed. The method allows the responses in the far-IR region caused by various electronic excitations in molecular or material systems to be observed in real time. Using the technique, the relaxation dynamics of the photo-excited carriers and electron/phonon coupling in bulk MoS2 are investigated. It is found that the photo-generation of excited carriers occurs within two hundred fs and the relaxation of the carriers is tens of ps. The electron-phonon coupling between the excitations of electrons and the phonon mode E1u of MoS2 is also directly observed. The electron excitation shifts the frequency of the phonon mode 9 cm−1 higher, resulting in an absorption peak at 391 cm−1 and a bleaching peak at 382 cm−1. The frequency shift diminishes with the relaxation of the carriers.engArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.Journal articlehttp://dx.doi.org/10.1063/1.4921573