148 citations · 1.2k across the 33 of their papers we have counts for
8 papers · 1 filter
Exceptional dynamics of interacting spin liquids
Kang Yang, Daniel Varjas, Emil J. Bergholtz +2
We show that interactions in quantum spin liquids can result in non-Hermitian phenomenology that differs qualitatively from mean-field expectations. We demonstrate this in two prom…
Topological Lattice Models with Constant Berry Curvature
Daniel Varjas, Ahmed Abouelkomsan, Kang Yang +1
Band geometry plays a substantial role in topological lattice models. The Berry curvature, which resembles the effect of magnetic field in reciprocal space, usually fluctuates thro…
Qsymm: Algorithmic symmetry finding and symmetric Hamiltonian generation
Daniel Varjas, Tomas O. Rosdahl, Anton R. Akhmerov
Symmetry is a guiding principle in physics that allows to generalize conclusions between many physical systems. In the ongoing search for new topological phases of matter, symmetry…
Space group constraints on weak indices in topological insulators
Daniel Varjas, Fernando de Juan, Yuan-Ming Lu
Lattice translation symmetry gives rise to a large class of "weak" topological insulators (TIs), characterized by translation-protected gapless surface states and dislocation bound…
Bulk invariants and topological response in insulators and superconductors with nonsymmorphic symmetries
Daniel Varjas, Fernando de Juan, Yuan-Ming Lu
In this work we consider whether nonsymmorphic symmetries such as a glide plane can protect the existence of topological crystalline insulators and superconductors in three dimensi…
Chiral Luttinger liquids and a generalized Luttinger's theorem in fractional quantum Hall edges via finite-entanglement scaling
Daniel Varjas, Michael P. Zaletel, Joel E. Moore
We use bosonic field theories and the infinite system density matrix renormalization group (iDMRG) method to study infinite strips of fractional quantum Hall (FQH) states starting…
Magnetoelasticity in ACr2O4 spinel oxides
V. Kocsis, S. Bordács, D. Varjas +6
Dynamical properties of the lattice structure was studied by optical spectroscopy in ACr2O4 chromium spinel oxide magnetic semiconductors over a broad temperature region of T=10-33…
Magnetic order induced crystal symmetry lowering in ACrO ferrimagnetic spinels
S. Bordacs, D. Varjas, I. Kezsmarki +6
We demonstrate that the onset of complex spin orders in ACrO spinels with magnetic ACo, Fe and Cu ions lowers the lattice symmetry. This is clearly indicated by the emer…