Observation of Dipolar Spin-ice--like Correlations in the Quantum Spin Ice Candidate Ce$_2$Sn$_2$O$_7$

Bo Yuan; M. Powell; X. Liu; J. Ni; E. M. Smith; R. Schäfer; R. Moessner; F. Ye; J. Dudemaine; A. D. Bianchi; J. W. Kolis; B. D. Gaulin

arXiv · 2601.20766

Observation of Dipolar Spin-ice--like Correlations in the Quantum Spin Ice Candidate Ce$_2$Sn$_2$O$_7$

Bo Yuan·M. Powell·X. Liu·J. Ni·E. M. Smith·R. Schäfer·R. Moessner·F. Ye·J. Dudemaine·A. D. Bianchi·J. W. Kolis·B. D. Gaulin

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Abstract

We report diffuse scattering measurements on the dipolar-octupolar pyrochlore, Ce$_2$Sn$_2$O$_7$, to elucidate its magnetic correlations within the correlated paramagnetic regime above its ordering temperature, $\mathrm{T_N}\sim 40~$mK. The magnetic transition at $\mathrm{T_N}$, observed in recent specific heat measurements, has been interpreted within the nearest-neighbor XYZ model as a transition into an all-in-all-out (AIAO) magnetic order. However, the observed diffuse scattering above $\mathrm{T_N}$ argues against an AIAO magnetic order by exhibiting $no$ short-range order at the AIAO wave-vectors, inconsistent with the nearest neighbor model. Instead, the observed diffuse scattering strongly resembles that observed in classical dipolar spin ice, Dy$_2$Ti$_2$O$_7$, and suggests the presence of short-range correlated structures such as chains, or clusters in the low energy manifold of Ce$_2$Sn$_2$O$_7$, favored by further neighbor interactions. We discuss how chain-like states qualitatively account for the observed H-T phase diagram under a [1,1,0]-field.

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Bo Yuan, M. Powell, X. Liu, J. Ni, E. M. Smith, R. Schäfer, R. Moessner, F. Ye, J. Dudemaine, A. D. Bianchi, J. W. Kolis, B. D. Gaulin. 2026-01-28. Observation of Dipolar Spin-ice--like Correlations in the Quantum Spin Ice Candidate Ce$_2$Sn$_2$O$_7$. https://arxiv.org/abs/2601.20766

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