Bouaziz Juba, Mendive-Tapia Eduardo, Blügel Stefan, Staunton Julie B
Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich, Germany.
Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom.
Phys Rev Lett. 2022 Apr 15;128(15):157206. doi: 10.1103/PhysRevLett.128.157206.
We show from first principles that barrel-shaped structures within the Fermi surface of the centrosymmetric intermetallic compounds GdRu_{2}Si_{2} and Gd_{2}PdSi_{3} give rise to Fermi surface nesting, which determines the strength and sign of quasi-two-dimensional Ruderman-Kittel-Kasuya-Yosida pairwise exchange interactions between the Gd moments. This is the principal mechanism leading to their helical single-q spin-spiral ground states, providing transition temperatures and magnetic periods in good agreement with experiment. Using atomistic spin-dynamic simulations, we draw a direct line between the subtleties of the three-dimensional Fermi surface topology and the stabilization of a square skyrmion lattice in GdRu_{2}Si_{2} at applied magnetic fields as observed in experiment.
我们从第一性原理出发表明，中心对称金属间化合物GdRu₂Si₂和Gd₂PdSi₃的费米面内的桶状结构会导致费米面嵌套，这决定了Gd磁矩之间准二维Ruderman-Kittel-Kasuya-Yosida成对交换相互作用的强度和符号。这是导致其螺旋单q自旋螺旋基态的主要机制，所提供的转变温度和磁周期与实验结果吻合良好。通过原子自旋动力学模拟，我们在三维费米面拓扑结构的细微之处与实验中观察到的在施加磁场时GdRu₂Si₂中方形斯格明子晶格的稳定性之间建立了直接联系。
