Exciton condensation in bilayer spin-orbit insulator

Exciton condensation in bilayer spin-orbit insulator

Blog Article

We investigate the nature of the magnetic excitations of a bilayer single-orbital Hubbard model in the intermediate-coupling regime.This model exhibits a quantum phase transition (QPT) between a paramagnetic (PM) and an insulating antiferromagnetic (AFM) phase at a critical value of the coupling strength.By using the random phase approximation, we show that the QPT is continuous when the PM state duospiritalis.com is a band insulator and that the corresponding quantum critical point (QCP) arises from the condensation of preformed excitons.

These low-energy excitons re-emerge on the other side of the QCP as the transverse and longitudinal modes vibrating table for chocolate of the AFM state.In particular, the longitudinal mode remains sharp for the model parameters relevant to Sr_{3}Ir_{2}O_{7} because of the strong easy-axis anisotropy of this material.