2026-04-09 合肥物質科学研究院(HFIPS)

Temperature dependence of phonon frequency and intensity (Image by QIU Kang)
<関連情報>
- https://english.hf.cas.cn/nr/rn/202604/t20260409_1155590.html
- https://journals.aps.org/prb/abstract/10.1103/6chp-2z42
短距離スピン秩序とスピンフォノン結合N1CrO2テラヘルツスペクトルによって明らかになった Short-range spin order and spin-phonon coupling in NaCrO2 revealed by terahertz spectra
Biwen Huang, Pengli Hao, and Zhigao Sheng
Physicl Review B Publishe 16 March, 2026
DOI: https://doi.org/10.1103/6chp-2z42
Abstract
Frustrated magnetic materials provide a fertile ground for exploring novel quantum states, wherein the interplay between spin and lattice degrees of freedom plays a pivotal yet underexplored role. Here, we employ terahertz (THz) time-domain spectroscopy to investigate the spin-lattice coupling and short-range spin correlations in NaCrO2, an =3/2 layered triangular-lattice Heisenberg antiferromagnet. Combined with superconducting quantum interference device magnetometry, our THz spectroscopy reveals the persistence of short-range magnetic order up to twice the long-range magnetic ordering temperature. Furthermore, several low-frequency phonon modes are identified in the THz spectra. Their temperature dependence manifests a strong spin-phonon coupling, characterized by abrupt changes in the intensity and frequency of the phonon absorption peaks at magnetic critical temperatures. Further analysis implies that this coupling is primarily driven by the exchange-interaction-induced modification of the Cr-O bonds. Our work provides direct evidence of spin-phonon coupling in a frustrated magnet and suggests new avenues for manipulating lattice dynamics in quantum materials.


