Hosoi Masashi, Zhang Emily Z, Patri Adarsh S, Kim Yong Baek
Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan.
Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada.
Phys Rev Lett. 2022 Aug 26;129(9):097202. doi: 10.1103/PhysRevLett.129.097202.
Recent experiments on Ce_{2}Zr_{2}O_{7} suggest that this material may host a novel form of quantum spin ice, a three-dimensional quantum spin liquid with an emergent photon. The Ce^{3+} local moments on the pyrochlore lattice are described by pseudospin-1/2 degrees of freedom, whose components transform as dipolar and octupolar moments under symmetry operations. In principle, there exist four possible quantum spin ice regimes, depending on whether the Ising component is in the dipolar or octupolar channel, and two possible flux configurations of the emergent gauge field. In this Letter, using exact diagonalization and molecular dynamics, we investigate the equal-time and dynamical spin structure factors in all four quantum spin ice regimes using quantum and classical calculations. Contrasting the distinct signatures of quantum and classical results for the four possible quantum spin ice regimes and elucidating the role of quantum fluctuations, we show that the quantum structure factor computed for the π-flux octupolar quantum spin ice regime is most compatible with the neutron scattering results on Ce_{2}Zr_{2}O_{7}.
近期对Ce₂Zr₂O₇的实验表明，这种材料可能包含一种新型的量子自旋冰，即一种带有涌现光子的三维量子自旋液体。烧绿石晶格上的Ce³⁺局域矩由赝自旋-1/2自由度描述，其分量在对称操作下表现为偶极矩和八极矩。原则上，根据伊辛分量是在偶极通道还是八极通道，以及涌现规范场的两种可能磁通构型，存在四种可能的量子自旋冰态。在本信函中，我们使用精确对角化和分子动力学方法，通过量子和经典计算研究了所有四种量子自旋冰态下的等时和动态自旋结构因子。对比四种可能量子自旋冰态下量子和经典结果的不同特征，并阐明量子涨落的作用，我们表明，为π-磁通八极量子自旋冰态计算的量子结构因子与Ce₂Zr₂O₇的中子散射结果最为相符。
