A phason disordered two dimensional quantum antiferromagnet
arXiv:0901.4441 · doi:10.1103/PhysRevB.79.172406
Abstract
We examine a novel type of disorder in quantum antiferromagnets. Our model consists of localized spins with antiferromagnetic exchanges on a bipartite quasiperiodic structure, which is geometrically disordered in such a way that no frustration is introduced. In the limit of zero disorder, the structure is the perfect Penrose rhombus tiling. This tiling is progressively disordered by augmenting the number of random "phason flips" or local tile-reshuffling operations. The ground state remains Néel ordered, and we have studied its properties as a function of increasing disorder using linear spin wave theory and quantum Monte Carlo. We find that the ground state energy decreases, indicating enhanced quantum fluctuations with increasing disorder. The magnon spectrum is progressively smoothed, and the effective spin wave velocity of low energy magnons increases with disorder. For large disorder, the ground state energy as well as the average staggered magnetization tend towards limiting values characteristic of this type of randomized tilings.
5 pages, 7 figures
References in corpus (8)
- Quantum Antiferromagnetism in Quasicrystals
- Self-assembly, structure and electronic properties of a quasiperiodic lead monolayer
- Quantum Fluctuations and Excitations in Antiferromagnetic Quasicrystals
- Penrose Quantum Antiferromagnet
- Spin waves and local magnetizations on the Penrose tiling
- Ground state of a two dimensional quasiperiodic antiferromagnet
- Energy levels and their correlations in quasicrystals
- Clusters, phason elasticity, and entropic stabilisation: a theory perspective
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- Electronic states of a disordered 2D quasiperiodic tiling: from critical states to Anderson localization
- Quasiperiodic Heisenberg antiferromagnets in two dimensions
- Doped Mott insulator on Penrose tiling
- Geometry fluctuations in a two-dimensional quantum antiferromagnet
- Host-atom-driven transformation of a honeycomb oxide into a dodecagonal quasicrystal
- Modulated honeycomb lattices and their magnetic properties