We investigate the quantum phases of higher-spin Kitaev models using advanced tensor network methods. By boosting the performance of gradient optimization of dense infinite projected entangled pair states (iPEPS) to bond dimensions beyond D>10 and environment dimensions \chi>500, and combining novel data analysis techniques, we uncover a new phase of matter in frustrated Kitaev-type magnets: a spontaneous valence-bond solid with topological order. For spin-1, spin-3/2, and spin-2 Kitaev models, we find distinct valence-bond ordered phases characterized by translational symmetry breaking with tripled unit cells. These phases correspond to plaquette order, topological dimer order, and non-topological dimer order, respectively. Our conclusions are supported by a cross-validation between unrestricted variational tensor network calculations and the detection of symmetry breaking via cat-state behavior in symmetry-restricted states. The origin of the different orders can also be understood from theoretical analysis. This work sheds light on the interplay between topological and symmetry-breaking orders and their detection using tensor network approaches.

Bio:
Dr. Yuchi He obtained his PhD in Physics from Carnegie Mellon University in 2020 and his BS from Peking University. He has held postdoctoral positions at RWTH Aachen University and the University of Oxford, and is currently a postdoctoral researcher at Ghent University and a visiting researcher at Oxford. His research interests focus on strongly correlated quantum many-body systems, explored using effective field theories and tensor network methods, with recent interests in twisted transition metal dichalcogenides and frustrated magnetism.

Contact: Lei Wang 9853