Abstract
The osmate pyrochlore Cd2Os2O7 supports an antiferromagnet insulator ground state with an all-in/all-out (AIAO) spin ordering at low temperature. Above 225 K, Cd2Os2O7 becomes a paramagnetic metal whereas the mechanism of this metal-to-insulator transition (MIT) remains elusive. In this letter, we use cryogenic near-field technique operating at terahertz frequencies to study the evolution of low-energy response across the MIT. We observed a systematic variation of the magnitude of nano-THz signal across the transition, consistent with the trend in the direct-current conductivity. Conducting domain walls that dominate the nano-scale landscape of the conductivity of a closely related AIAO system Nd2Ir2O7 are not apparent in Cd2Os2O7.
Original language | English (US) |
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Article number | 56001 |
Journal | EPL |
Volume | 137 |
Issue number | 5 |
DOIs | |
State | Published - Mar 2022 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:Copyright © 2022 The author(s).