Figure 3: The FFT spectrum calculated for the thermoelectric power data at T=1.7 K.

Inset shows the low-frequency part, where peaks are attributed to F1, F2 and F3 frequencies as well as higher harmonics of F2.
Inset shows the low-frequency part, where peaks are attributed to F1, F2 and F3 frequencies as well as higher harmonics of F2.