First-Principles Prediction of Room Temperature Quantum Anomalous Hall Effect in 2D Oxalate-Bridged Metal Organic Complexes

Quantum anomalous Hall (QAH) insulators are a highly promising class of materials for spintronic devices and quantum computations because of their precise quantization nature, robust properties against defects, and relatively low energy consumption for operation. To realize the QAH effect, quantum spin Hall (QSH) insulators must be utilized, which requires transition metal doping or surface functionality control. Here, we propose a new family of high temperature organic QAH insulators of 2D oxalate-bridged metal (M) organic complexes, M₂(C₂O₄)₃ (M=Re, Pt, Hg). First-principles calculations show the spin–orbit coupling gaps ~160 meV, with Curie temperature, calculated by non-linear spin wave theory based on the XYZ Heisenberg model, of greater than ~380 K, which indicates a room-temperature QAH effect. The first room-temperature organic QAH insulators with computationally proved high thermal stability can be realized experimentally.