Snedden, E.W. Jamison, S.P. Walsh, D.A. JACoW Geneva, Switzerland 978-3-95450-177-9 10.18429/JACoW-IBIC2016-WEPG53 English 768-771 WEPG53 radiation electron laser diagnostics framework Contribution to a conference proceedings 2017 2017-02 http://dx.doi.org/10.18429/JACoW-IBIC2016-WEPG53 http://jacow.org/ibic2016/papers/wepg53.pdf We demonstrate a method for full and unambiguous temporal characterization of few-cycle electromagnetic pulses, including retrieval of the carrier envelope phase (CEP), in which the interference between non-linear frequency mixing components is spectrally resolved using Frequency Resolved Optical Gating (FROG). We term this process Real-Domain FROG (ReD-FROG) and demonstrate its capabilities through the complete measurement of the temporal profile of a single-cycle THz pulse. When applied at THz frequencies ReD-FROG overcomes the bandwidth limitations relating probe and test pulses in Electro-Optic (EO) sampling. The approach can however be extended generally to any frequency range and we provide a conceptual demonstration of the CEP retrieval of few-cycle optical field.