Desrochers Félix, Kim Yong Baek
Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada.
Phys Rev Lett. 2024 Feb 9;132(6):066502. doi: 10.1103/PhysRevLett.132.066502.
Recent investigations on the dipolar-octupolar compounds Ce_{2}Zr_{2}O_{7} and Ce_{2}Sn_{2}O_{7} suggest that they may stabilize so-called π-flux octupolar quantum spin ice (π-O-QSI), a novel three-dimensional quantum spin liquid hosting emergent photons. Confirmation of such an exotic phase would require the prediction of a distinctive signature and its subsequent experimental observation. So far, however, theoretical predictions for any such sharp smoking-gun signatures are lacking. In this Letter, we thoroughly investigate O-QSI using an extension of gauge mean-field theory. This framework produces a phase diagram consistent with previous work and an energy-integrated neutron scattering signal with intensity-modulated rod motifs, as reported in experiments and numerical studies. We predict that the dynamical spin structure factor of π-O-QSI is characterized by a broad continuum with three distinctive peaks as a consequence of the two mostly flat spinon bands. These three peaks should be measurable by high-resolution inelastic neutron scattering. Such spectroscopic signatures would be clear evidence for the realization of π-flux quantum spin ice.
最近对偶极 - 八极化合物Ce₂Zr₂O₇和Ce₂Sn₂O₇的研究表明，它们可能会稳定所谓的π - 通量八极量子自旋冰（π - O - QSI），这是一种新型的三维量子自旋液体，其中存在涌现光子。要确认这样一个奇异相，需要预测其独特特征并随后进行实验观测。然而，到目前为止，还缺乏对任何此类明确确凿特征的理论预测。在这篇快报中，我们使用规范平均场理论的扩展对O - QSI进行了全面研究。这个框架产生了一个与先前工作一致的相图，以及一个如实验和数值研究中所报道的具有强度调制棒状图案的能量积分中子散射信号。我们预测，由于两个几乎平坦的自旋子能带，π - O - QSI的动态自旋结构因子的特征是具有三个独特峰的宽连续谱。这三个峰应该可以通过高分辨率非弹性中子散射测量。这样的光谱特征将是实现π - 通量量子自旋冰的明确证据。
