Apr 9, 2025
4:15pm - 4:30pm
Summit, Level 4, Room 440
Hyeon Han1
Pohang University of Science and Technology1
Defects in oxides, such as oxygen vacancies and ion interstitials, play a crucial role in inducing new phases and giving rise to intriguing electrical and magnetic properties. In this presentation, I will demonstrate the suppression of octahedral tilting and altered magnetism in ferromagnetic SrRuO
3 thin films via hydrogen spillover [1]. The film further shows the reversal of anomalous Hall effects, enabling a topological Hell effect-like hump signal through hydrogenation. In addition, I will present the first realization of the epitaxial growth of
T-Nb
2O
5 thin films, which feature vertical 2D ionic transport channels [2]. These vertical 2D channels enable rapid Li-ion migration into the film in addition to a colossal insulator-metal transition, where resistivity decreases by 11 orders of magnitude due to the electron population of the initially empty Nb 4d
0 states. This study paves the way for controlling emergent physical phenomena in correlated oxide thin films and advancing the development of iontronic materials and devices.
[1] H. Han* et al., Adv. Mater. 35, 2207246 (2023)
[2] H. Han* et al., Nat. Mater. 22, 1128-1135 (2023)