In this work, Li et al. report a paramagnetic-fluid-constructed liquid microrobot. The microrobot is reversible between paramagnetic-ferromagnetic transitions under a magnetic field. Furthermore, the deformation degrees of the microrobot can be varied based on the structure of its surroundings, which equips these microrobots with on-board imaging and sensing abilities.

Liu et al. demonstrate that the ferromagnetic perovskite oxides with high TC above 600 K in BaFeO3-δ single-crystalline thin films fabricated by oxygen stoichiometry engineering. This significantly raises the TC of a ferromagnet with a single cubic perovskite structure, which is important for technological implementations at room temperature.