Chen Lu, Lefrançois Étienne, Vallipuram Ashvini, Barthélemy Quentin, Ataei Amirreza, Yao Weiliang, Li Yuan, Taillefer Louis
Institut quantique, Département de physique & RQMP, Université de Sherbrooke, Sherbrooke, QC, Canada.
International Center for Quantum Materials, School of Physics, Peking University, Beijing, China.
Nat Commun. 2024 Apr 25;15(1):3513. doi: 10.1038/s41467-024-47858-5.
The thermal Hall effect has emerged as a potential probe of exotic excitations in spin liquids. In the Kitaev magnet -RuCl, the thermal Hall conductivity has been attributed to Majorana fermions, chiral magnons, or phonons. Theoretically, the former two types of heat carriers can generate a "planar" , whereby the magnetic field is parallel to the heat current, but it is unknown whether phonons also could. Here we show that a planar is present in another Kitaev candidate material, NaCoTeO. Based on the striking similarity between and the phonon-dominated thermal conductivity , we attribute the effect to phonons. We observe a large difference in between different configurations of heat current and magnetic field, which reveals that the direction of heat current matters in determining the planar . Our observation calls for a re-evaluation of the planar observed in -RuCl.
热霍尔效应已成为探测自旋液体中奇异激发的一种潜在手段。在基泰耶磁体——RuCl中，热霍尔电导率已被归因于马约拉纳费米子、手性磁振子或声子。从理论上讲，前两种热载流子可以产生一个“平面”热霍尔电导率，即磁场与热流平行，但声子是否也能如此尚不清楚。在这里，我们表明在另一种基泰耶候选材料NaCoTeO中存在平面热霍尔电导率。基于热霍尔电导率与以声子为主的热导率之间的显著相似性，我们将这种效应归因于声子。我们观察到热流和磁场的不同配置之间热霍尔电导率存在很大差异，这表明热流方向在确定平面热霍尔电导率方面很重要。我们的观察结果要求对在RuCl中观察到的平面热霍尔电导率进行重新评估。
