Enhanced magnetoelectric effect near a field-driven zero-temperature quantum phase transition of the spin-1/2 Heisenberg-Ising ladder

TL;DR

This paper investigates how external electric and magnetic fields influence the magnetoelectric effect and quantum phase transitions in a spin-1/2 Heisenberg-Ising ladder, revealing critical behavior and phase transition characteristics.

Contribution

It provides a rigorous analysis of electric field control over quantum phase transitions and details the critical behavior of magnetoelectric properties in the model.

Findings

Electric field controls the transition between Ne9el and paramagnetic phases.

Staggered magnetization vanishes with Ising critical exponent 1/8.

Electric polarization shows a weak singularity at the transition.

Abstract

Magnetoelectric effect of the spin-1/2 Heisenberg-Ising ladder in a presence of the external electric and magnetic fields is rigorously examined by taking into account Katsura-Nagaosa-Balatsky mechanism. It is shown that the applied electric field may control a quantum phase transition between the N\'eel (stripy) ordered phase and the disordered paramagnetic phase. The staggered magnetization vanishes according to a power law with the Ising-type critical exponent 1/8, the electric polarization exhibits a weak singularity and the dielectric susceptibility shows a logarithmic divergence at this particular quantum phase transition. The external electric field may alternatively invoke a discontinuous phase transition accompanied with abrupt jumps of the dielectric polarization and susceptibility on assumption that the external magnetic field becomes nonzero.