A paper describing Questaal's functionality, including its basis set, its various implementations of density-functional theory and its two tracks of many-body theory.
We are pleased to announce the 3rd Daresbury Questaal school. It will take place 13-17 May 2019, at Daresbury Laboratory, UK. This is an opportunity for researchers to learn about advanced electronic structure and gain hands-on experience with Questaal's DFT/QSGW/BSE/DMFT functionality. The event is free to attend and local accommodation will be provided.
We have demonstrated the feasibility of calculating the spin-orbit torques in layered systems within density-functional theory, augmented by an Anderson model to treat disorder. Terms beyond the usual damping-like and field-like torques were found. While the torques that contribute to damping are almost entirely due to spin-orbit coupling on the Pt atoms, the field-like torque does not require it.
The Quasiparticle Self-Consistent GW approximation is combined with Dynamical Mean Field theory (DMFT). It is shown that by varying the positions of apical oxygen atoms, a metal-insulator transition can be induced in La2CuO4. This work also shows that optical conductivity can be well predicted by the theory and shows how spin and charge susceptibilities and the superconducting pairing order parameter, vary with the apical O displacement. QSGW+DMFT provides a new approach to handle strong correlations with predictive capability greatly superior to conventional methods such as DFT+DMFT.
A hands-on course highlighting Questaal's GW/DMFT/BSE capability. This is an opportunity for researchers to learn about advanced electronic structure and how to use the Questaal Suite.
The Lambrecht group at Case Western University estimated how phonons modify the band structure in SrTiO3. Isolating the Frolich part of the electron-phonon interaction (which is the dominant contribution for highly polar compounds), they estimated the reduction in the screened coulomb interaction W, and its effect on the QSGW band structure.