Pressure-tuning the quantum spin Hamiltonian of the triangular lattice antiferromagnet Cs2CuCl4
Pressure-tuning the quantum spin Hamiltonian of the triangular lattice antiferromagnet Cs2CuCl4
复制标题
压力调节三角晶格反铁磁体 Cs2CuCl4 的量子自旋哈密顿量
DOI：
10.1038/s41467-019-09071-7
复制
发表时间：
2019
影响因子：
16.6
通讯作者：
H. Tanaka
中科院分区：
文献类型：
--
作者：
S.A. Zvyagin;D. Graf;T. Sakurai;S. Kimura;H. Nojiri;J. Wosnitza;H. Ohta;T. Ono;H. Tanaka
量子三角晶格反铁磁体是研究凝聚态物质中几何挫败的众多现象的重要原型系统。除了极不寻常的磁性外，它们还拥有丰富的相图（从不受挫的方形晶格到量子自旋液体），但尚未得到实验证实。这一研究领域的一个主要障碍是缺乏具有适当（理想调整）磁参数的材料。使用 Cs2CuCl4 作为模型系统，我们演示了一种替代方法，其中，自旋哈密顿量通过静水压力改变，而不是化学成分。该方法结合了高压电子自旋共振和射频。磁化率测量，使我们不仅能够准连续地调整交换参数，而且能够准确地监测它们。我们的实验表明，在 1.8GPa 压力下，交换耦合比从 0.3 大幅增加到 0.42，揭示了许多新兴的场诱导相。
Quantum triangular-lattice antiferromagnets are important prototype systems to investigate numerous phenomena of the geometrical frustration in condensed matter. Apart from highly unusual magnetic properties, they possess a rich phase diagram (ranging from an unfrustrated square lattice to a quantum spin liquid), yet to be confirmed experimentally. One major obstacle in this area of research is the lack of materials with appropriate (ideally tuned) magnetic parameters. Using Cs2CuCl4as a model system, we demonstrate an alternative approach, where, instead of the chemical composition, the spin Hamiltonian is altered by hydrostatic pressure. The approach combines high-pressure electron spin resonance and r.f. susceptibility measurements, allowing us not only to quasi-continuously tune the exchange parameters, but also to accurately monitor them. Our experiments indicate a substantial increase of the exchange coupling ratio from 0.3 to 0.42 at a pressure of 1.8 GPa, revealing a number of emergent field-induced phases.