We study magnetic textures realized in noncentrosymmetric Kondo lattice models in which localized magnetic moments weakly interact with itinerant electrons subject to Rashba and Dresselhaus spin-orbit couplings. By virtue of state-of-the-art numerical simulations as well as variational calculations, we uncover versatile multiple-$Q$ orderings under a zero magnetic field, which are found to originate in the instabilities of the Fermi surface whose spin degeneracy is lifted by the spin-orbit couplings. In the case with equally strong Rashba and Dresselhaus spin-orbit couplings, which is known to realize a persistent spin helix in semiconductor quantum wells, we discover a sextuple-$Q$ magnetic ordering with a checkerboardlike spatial pattern of the spin scalar chirality. In the presence of either Rashba or Dresselhaus spin-orbit coupling, we find another multiple-$Q$ ordering, which is distinct from skyrmion crystals discussed under the same symmetry. Our results indicate that the cooperation of the spin-charge and spin-orbit couplings brings about richer magnetic textures than those studied within effective spin models. The situations would be experimentally realized, e.g., in noncentrosymmetric heavy-fermion compounds and heterostructures of spin-orbit-coupled metals and magnetic insulators.

• Received 20 September 2018
• Revised 19 November 2018

DOI:https://doi.org/10.1103/PhysRevB.98.224406