Manipulating terahertz responses of GdFeO3 ceramics by thickening and thermal methods

Abstract Electric field-induced antiferromagnets with ultrahigh resonant frequencies without current flow in insulating materials is highly desired. This paper reports the terahertz (THz) responses of Γ4 in rare-earth orthoferrite GdFeO3 ceramics, which were manipulated using thickening and thermal methods. As the thickness was increased, the noise was greatly reduced, and increased peak heights of both the ferromagnetic resonances and antiferromagnetic resonances were observed. For the thermal control of THz responses in GdFeO3, the resonant frequencies of both the ferromagnetic resonances and antiferromagnetic resonances experienced a blue shift, and their peak heights increased. The detected shifts of the responses were determined by the changes in thermodynamic potential. Moreover, macroscopic properties were collected to verify the coexistence of ferromagnetism and antiferromagnetism.