Xu Changsong, Feng Junsheng, Kawamura Mitsuaki, Yamaji Youhei, Nahas Yousra, Prokhorenko Sergei, Qi Yang, Xiang Hongjun, Bellaiche L
Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA.
Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433, People's Republic of China.
Phys Rev Lett. 2020 Feb 28;124(8):087205. doi: 10.1103/PhysRevLett.124.087205.
Quantum spin liquids (QSLs) form an extremely unusual magnetic state in which the spins are highly correlated and fluctuate coherently down to the lowest temperatures, but without symmetry breaking and without the formation of any static long-range-ordered magnetism. Such intriguing phenomena are not only of great fundamental relevance in themselves, but also hold promise for quantum computing and quantum information. Among different types of QSLs, the exactly solvable Kitaev model is attracting much attention, with most proposed candidate materials, e.g., RuCl_{3} and Na_{2}IrO_{3}, having an effective S=1/2 spin value. Here, via extensive first-principles-based simulations, we report the investigation of the Kitaev physics and possible Kitaev QSL state in epitaxially strained Cr-based monolayers, such as CrSiTe_{3}, that rather possess a S=3/2 spin value. Our study thus extends the playground of Kitaev physics and QSLs to 3d transition metal compounds.
量子自旋液体（QSLs）形成了一种极其特殊的磁态，其中自旋高度相关且在极低温度下仍能相干波动，但不存在对称性破缺，也不形成任何静态的长程有序磁性。这类有趣的现象不仅本身具有重大的基础意义，而且在量子计算和量子信息方面也颇具前景。在不同类型的QSLs中，可精确求解的Kitaev模型备受关注，大多数被提出的候选材料，例如RuCl₃和Na₂IrO₃，具有有效的S = 1/2自旋值。在此，通过基于第一性原理的广泛模拟，我们报告了对外延应变的Cr基单层（如CrSiTe₃）中Kitaev物理特性和可能的Kitaev QSL态的研究，这些单层实际上具有S = 3/2自旋值。我们的研究因此将Kitaev物理和QSLs的研究范围扩展到了三维过渡金属化合物。
