fig1

Figure 1. A: A DENSsolutions Lightning Arctic TEM holder for in situ biasing, heating, and cryo- experiments. The tip of the holder is internally connected to the metallic cooling braid that is immersed in liquid nitrogen, as depicted by the blue dashed line; B: thermo Fisher-compatible heating and biasing nano-chip for in situ TEM experiments. The scale bar is 2 mm; C: a representative SEM image of the FIB-prepared single-crystal BTO specimen on the nano-chip. A carbon protection layer (marked as FIB-C) was deposited on the top of BTO sample. The scale bar is 2 µm; D-F: finite element analysis simulations of the temperature distribution in the sample area during heating at a few set temperatures, namely -174 °C, -57 °C and 215 °C while the holder is being cooled. The scale bars are 100 µm. TEM: transmission electron microscopy; BTO: BaTiO₃; FIB: focused ion beam; SEM:scanning electron microscope.