Add to ORKGIn recent years, frequency-resolved optical gating (FROG) technique has been widely applied for ultrashort pulse characterization. A number of outstanding qualities such as experimental simplicity, uniqueness of the retrieved amplitude and phase, and independent data checks make FROG an invaluable tool in ultra-fast spectroscopy. In this contribution we introduce a new member of the FROG family: frequency-resolved pump-probe (FRPP). Unlike optically heterodyne detected (OHD) FROG, which requires additional polarizers, FRPP employs unmodified pump-probe geometry widely used in ultrafast spectroscopic experiments. Furthermore, a FRPP trace carries both positive and negative values, which should substantially improve the noise stability of the...