[9p-Z17-1~22] 3.1 Basic optics and frontier of optics

▲ [9p-Z17-4] Terahertz Magneto-Spectroscopy Mapping of the Low-Temperature Phase Transition of Er_xY_1-xFeO₃

〇(D)Nicolas Marquez Peraca¹, Xinwei Li¹, Motoaki Bamba^2,3, Chien-Lung Huang¹, Xiaoxuan Ma⁴, Takuma Makihara¹, Emilia Morosan¹, Shixun Cao⁴, Junichiro Kono¹ (1.Rice University, 2.Kyoto University, 3.PRESTO, 4.Shanghai University)

Keywords:ultrastrong, terahertz, orthoferrites

In this work, we have studied the low temperature properties of the rare-earth orthoferrite Er_xY_1-xFeO₃ using terahertz (THz) time-domain magnetospectroscopy. Comparison of the theoretical predictions with actual observations revealed that the phase transition this material exhibits can be modeled using an extended Dicke Hamiltonian that incorporates short-range Er-Er exchange interactions, broadening our understanding of the role of cooperative effects in the superradiant phase transition.