Interferometric characterization of pulse front tilt of spatiotemporally   focused femtosecond laser pulses for three-dimensional micromachining   application
  We report on an experimental measurement of the pulse front tilt (PFT) of spatiotemporally focused femtosecond laser pulses in the focal plane in both air and bulk transparent materials, which is achieved by examination of the interference pattern between the spatiotemporally focused pulse and a conventional focused reference pulse as a function of time delay between the two pulses. Our simulation results agree well with the experimental observations. 
Zhaohui Wang, Fei He, Jielei Ni, Chenrui Jing, Hongqiang Xie, Bin   Zeng, Wei Chu, Lingling Qiao, and Ya Cheng
physics.optics