Figure 3. Experimental and theoretical field-effect mobility and band structures of CH₃NH₃PbI₃.

(a) Temperature dependence of field-effect electron and hole mobilities, extracted from the forward sweeping of transfer characteristics at V_ds=20 V and V_ds=−20 V, respectively. (b) Calculated temperature dependence hole (red curves) and electron (black curves) mobility in tetragonal (T=300 to 160 K) and orthorhombic (T=160 to 77 K) phases of CH₃NH₃PbI₃. The crystal unit cells of the two phases are shown as insets. (c, d) Band structures of the tetragonal (c) and orthorhombic (d) phases obtained by DFT-Perdew–Burke–Ernzerhof method with (solid curves) and without (dotted curves; W/o) spin-orbital coupling (SOC).