Fig. 1. (a) Measured plasma-mirror FROG trace. The VUV pulse generated in the Ar cell passes the LiF lens prior to the plasma-mirror reflection. (b) FROG trace retrieved with the LSGPA. The FROG error is $G=0.058472$. The size of the FROG traces is $256\times 210$ pixels.

Fig. 2. Temporal waveform of the VUV pulse extracted from the plasma-mirror FROG trace in Figure 1(a) by (a) the LSGPA and (b) the PCGPA. The solid and dotted lines indicate the intensity and relative phase, respectively. The intensity is normalized at the maximum.

Fig. 3. Plasma-mirror reflectivity difference, $R(t)-R_{0}$, extracted from the plasma-mirror FROG trace in Figure 1(a) based on (a) the LSGPA and (b) the PCGPA.

Fig. 4. Measured plasma-mirror FROG trace. The VUV pulse generated in the Ar cell passes the LiF lens and the $\text{CaF}_{2}$ plate prior to the plasma-mirror reflection. (b) FROG trace retrieved with the LSGPA. The FROG error is $G=0.037868$. The size of the FROG traces is $256\times 330$ pixels.

Fig. 5. (a) Temporal and (b) spectral waveform of the VUV pulse extracted from the plasma-mirror FROG trace in Figure 4(a) based on the LSGPA. The solid and dotted lines indicate the intensity and relative phase, respectively. The intensity is normalized at the maximum. The GDD induced by the LiF lens and the $\text{CaF}_{2}$ plate is plotted as a grey line in (b).

Fig. 6. Plasma-mirror reflectivity difference, $R(t)-R_{0}$, extracted from the plasma-mirror FROG trace in Figure 4(a) based on the LSGPA.