Abstract
We study the zero-temperature phase diagram of the spin-1/2 Heisenberg model with breathing anisotropy (i.e., with different coupling strength on the upward and downward triangles) on the kagome lattice. Our study relies on large scale tensor network simulations based on infinite projected entangled-pair state and infinite projected entangled-simplex state methods adapted to the kagome lattice. Our energy analysis suggests that the U(1) algebraic quantum spin-liquid (QSL) ground-state of the isotropic Heisenberg model is stable up to very large breathing anisotropy until it breaks down to a critical lattice-nematic phase that breaks rotational symmetry in real space through a first-order quantum phase transition. Our results also provide further insight into the recent experiment on vanadium oxyfluoride compounds which has been shown to be relevant platforms for realizing QSL in the presence of breathing anisotropy.
Highlights
Quantum spin-liquids [1] are exotic phases of matter with highly entangled ground-states and fractionalized excitations which fall beyond the Ginzburg-Landau paradigm [2,3,4]
Our results suggest that the U(1) quantum spin-liquid (QSL) phase of the isotropic kagome Heisenberg antiferromagnet is stable up to very large breathing anisotropy J /J ≈ 0.05 and that, for larger anisotropy, it undergoes a first-order quantum phase transition (QPT) to a critical lattice-nematic phase
We are not able to calculate the same information within the framework of our tensor network (TN) simulations, we provided evidences through the paper that our results are in agreement with these density matrix renormalization group (DMRG) calculations of Ref. [44] and we believe that the gapless state we capture at the isotropic point should be a U(1) spin liquid
Summary
Quantum spin-liquids [1] are exotic phases of matter with highly entangled ground-states and fractionalized excitations which fall beyond the Ginzburg-Landau paradigm [2,3,4]. While early density matrix renormalization group (DMRG) results predicted a 2 gapped spin-liquid [11, 25, 26], variational Monte Carlo (VMC) calculations based on Gutzwiller projected fermionic wave functions favoured the existence of a U(1) gapless spin-liquid with algebraic decay of correlations [23, 24, 30, 31]. 1 2 breathing-kagome Heisenberg problem and study, in detail, the full phase diagram and groundstate properties of the BKH model in the thermodynamic limit, by resorting to large-scale tensor network calculations based on infinite projected entangled-pair state (iPEPS) [45,46,47,48] and. Our results suggest that the U(1) QSL phase of the isotropic kagome Heisenberg antiferromagnet is stable up to very large breathing anisotropy J /J ≈ 0.05 and that, for larger anisotropy, it undergoes a first-order quantum phase transition (QPT) to a critical lattice-nematic phase.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
