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arXiv · 2604.25436

Highly fluctuating double-$q$ magnetic order in the van der Waals metal CeTe$_3$

Ryutaro Okuma·Yuita Fujisawa·Natsumi Maekawa·Akiko Nakao·Yoshihisa Ishikawa·Riki Kobayashi·Yoshinori Okada·Daichi Ueta
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Abstract

CeTe$_3$ is a van der Waals antiferromagnet composed of magnetic [CeTe]$^+$ layers coupled to highly conducting Te$^{0.5-}$ square nets. Its simple quasi-two-dimensional electronic structure and cleavable nature make it an appealing platform for exploring correlated magnetism in reduced dimensions. To clarify the nature of its low-temperature state, we performed single-crystal neutron diffraction down to 0.3 K, complemented by scanning tunneling microscopy. A magnetic transition near 1.5 K gives rise to incommensurate Bragg peaks at $q_{\pm}\sim(\pm0.17,0,0.31)$, consistent with a double-$q$ magnetic order whose moments are predominantly aligned along the $c$ axis. The strongly reduced ordered moment is consistent with enhanced quantum fluctuations driven by $c$-$f$ hybridization, while the deviation of the propagation vectors from simple nesting suggests a coupling to residual charge-density-wave instabilities of the quasi-one-dimensional Te-derived bands. These results indicate that CeTe$_3$ hosts a correlated magnetic ground state where spin and itinerant charge degrees of freedom are intimately linked in the van der Waals limit.

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Ryutaro Okuma, Yuita Fujisawa, Natsumi Maekawa, Akiko Nakao, Yoshihisa Ishikawa, Riki Kobayashi, Yoshinori Okada, Daichi Ueta. 2026-04-28. Highly fluctuating double-$q$ magnetic order in the van der Waals metal CeTe$_3$. https://doi.org/10.1103/m9lb-4vhx

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