Room Temperature Direct Band Gap Emission from Ge p-i-n Heterojunction Photodiodes : Figure 4

Figure 4: Comparison of EL (black) and PL (blue) from the same diode. The energy positions of indirect (0.67 eV) and direct transition from intrinsic Ge (0.8 eV) and n⁺-type doped Ge (0.73 eV) are marked.