Flux mobility delocalization in the Kitaev spin ladder

Abstract

We study the Kitaev spin-$1/2$ ladder, a model which exhibits self-localization due to fractionalization caused by exchange frustration. When a weak magnetic field is applied, the model is described by an effective fermionic Hamiltonian, with an additional time reversal symmetry breaking term. We show that this term alone is not capable of delocalizing the system but flux mobility is a prerequisite. For magnetic fields larger but comparable to the flux gap, fluxes become mobile and drive the system into a delocalized regime, featuring finite dc transport coefficients. Our findings are based on numerical techniques, exact diagonalization and dynamical quantum typicality, from which, we present results for the specific heat, the dynamical energy current correlation function, as well as the inverse participation ratio, contrasting the spin against the fermion representation. Implications of our results for two-dimensional extensions of the model will be speculated on.

7 pages, 4 figures

References in corpus (15)

• Many body localization and thermalization in quantum statistical mechanics
• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Anderson Transitions
• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Topological characterization of quantum phase transitions in a S=1/2 spin model
• Exact results on the Kitaev model on a hexagonal lattice: spin states, string and brane correlators, and anyonic excitations
• Vaporization of Kitaev spin liquids
• Many-body localization dynamics from gauge invariance
• Microscopic mechanism for higher-spin Kitaev model
• Spin-S Kitaev model: Classical Ground States, Order by Disorder and Exact Correlation Functions
• Dynamics in many-body localized quantum systems without disorder
• Scenario for delocalization in translation invariant systems
• The Heart of Entanglement: Chiral, Nematic, and Incommensurate Phases in the Kitaev-Gamma Ladder in a Field
• Ground state and low-energy excitations of the Kitaev-Heisenberg ladder
• Thermal transport in a two-dimensional ${\mathbb{Z}}_2$ spin liquid

Cited by in corpus (9)

• Beyond Kitaev physics in strong spin-orbit coupled magnets
• Unusual excitations and double-peak specific heat in a bond-alternating spin-$1$ $K$-$\Gamma$ chain
• Insights into the Anisotropic Spin-$S$ Kitaev Chain
• Spin dynamics of the generalized quantum spin compass chain
• Emergent glassiness in disorder-free Kitaev model: Density matrix renormalization group study on a one-dimensional ladder setting
• Phase diagrams of spin-$S$ Kitaev ladders
• Finite-momentum energy dynamics in a Kitaev magnet
• Continuous phase transition from a chiral spin state to collinear magnetic order in a zigzag chain with Kitaev interactions
• Fractional Wannier Orbitals and Tight-Binding Gauge Fields for Kitaev Honeycomb Superlattices with Flat Majorana Bands