THz transient dynamics of Te/Ge and Ge/Te heterojunctions are shown in Fig. 1a. The X-ray photoelectron spectroscopy (XPS) spectrum of Te nanofilm exhibits two obvious peaks with the binding energies of 573.2 and 583.9 eV, which are assigned to Te 3d 5/2 and E 3d 3/2. It is found that the MD of Te (100 nm) is 14.5% even at an extremely low