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- About
- News
- Functionality
- Documentation
- Tutorials
- Tutorial Index
- Overview
- Generating Input Files
- DFT
- Basic Introduction: Si
- Detailed Introduction: Lead Telluride
- Detailed Introduction: The Input File
- Plotting Energy Bands
- Finding Extremal Points and Effective Mass
- Making Partial Densities-of-States and EELS
- Plotting Charge Densities
- Performing Molecular Statics
- lmf Basis Set and Convergence
- Adding Augmented Plane Waves
- Basis Set Optimisation
- Heisenberg Exchange Parameters

- GW
- QSGW + DMFT
- QSGW+DMFT with TRIQS
- Loading the QSGW Hamiltoninan in a Python Notebook
- Introduction
- Setting up the DMFT Loop
- Running the DMFT Loop
- Issues with Input and Parameters
- Charge + Static-magnetic Contributions
- The Density Loop
- The Maximum Entropy Method
- The Self-energy Loop and the Dynamical Double-counting
- Analyzing Spectral Functions

- Tight Binding
- DFT-ASA
- ASA Crystal Green Functions
- ASA Layer Green Functions
- Physical Application
- Miscellaneous

- Workshops

- Examples ›
**Why TiSe**_{2}is a band insulator, not an excitonic insulator - Workshop ›
**5th Questaal School** - Examples ›
**First principles vs second principles description of strongly correlated systems** - Examples ›
**Origins of Superconductivity in FeSe** - Examples ›
**Excitons in Cr{Cl,Br,I}₃**A QSGW description of the electronic structure and excitons in ferromagnetic CrX₃ compounds**Read More›** - Examples ›
**An embedding scheme within the Quasiparticle Self-consistent GW approximation**An efficient, high-fidelity scheme to obtain the properties of a localized defect embedded in an otherwise periodic host**Read More›** - Workshop ›
**4th Daresbury Questaal School** - Examples ›
**First-principles supercurrent calculations in realistic magnetic Josephson junctions**Detailed electronic structure calculations for a proper description of the transport properties of magnetic Josephson junctions**Read More›** - Examples ›
**Magnetism of Yttrium Iron Garnet**QSGW provides a parameter free description of magnetism in the YIG, the model material for spintronics and magnonics research**Read More›** - Examples ›
**Origins of Superconductivity in LaFe**_{2}As_{2}and CaFe_{2}As_{2} - News ›
**Questaal Methods Paper**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.**Read More›** - Examples ›
**Ab initio Description of Superconductivity in Sr**_{2}RuO_{4}How spin and charge parity combine to increase the superconducting critical temperature in Sr2RuO4 under strain**Read More›** - Examples ›
**Density-functional Description of Spin Orbit Torque**Interfacial contribution to spin-orbit torque and magnetoresistance in ferromagnet/heavy-metal bilayers**Read More›** - Examples ›
**Electrical transport of tetragonal CuMnAs**TB-LMTO-CPA was used to model electrical transport in tetragonal CuMnAs at finite temperature.**Read More›** - Examples ›
**Hyperbolic Optical Dispersion in CuS**Anisotropic Plasmonic CuS Nanocrystals as a Natural Electronic Material with Hyperbolic Optical Dispersion**Read More›** - Examples ›
**Energy band structure and optical properties of boron arsenide**State-of-the-art calculation of the electronic and optical properties of the newly emerging thermal transport semiconductor boron arsenide**Read More›** - Workshop ›
**3rd Daresbury Questaal school**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.**Read More›** - Examples ›
**Spin-orbit Torques in CoPt Multilayers**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.**Read More›** - Examples ›
**Metal-insulator transition in copper oxides induced by apex displacements**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.**Read More›** - Workshop ›
**Many body response functions in the Questaal code**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.**Read More›** - news ›
**Frolich contribution to energy band shifts in SrTiO**_{3}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.**Read More›** - news ›
**Ladder Diagrams in QSGW**Recently, Brian Cunningham and Myrta Gruening incorporated ladder diagrams as an extension to the RPA polarizability. Ladder diagrams significantly improve agreement with experimental dielectric response functions. The QSGW framework makes it possible to address systems whose electronic structure is poorly described within the standard perturbative GW approaches with as a starting point density-functional theory calculations. The Figure shows the real and imaginary parts of the dielectric function for Ge.**Read More›** - Examples ›
**Quasiparticle Self-Consistent GW**Metal-organic perovskite solar cells, CH3NH3PbI3 (MAPI) in particular, have attracted much attention recently because of their high power conversion efficiency and potential low cost.**Read More›** - Examples ›
**QSGW + Spin-Dynamical Mean Field Theory Applied to Ni**Density-Functional theory, while being immensely popular thanks to its simplicity, nevertheless is limited in its reliability. The QuasiParticle Self-Consistent GW approximation, while more demanding than DFT, is vastly more reliable than DFT, or GW theory based on DFT, for calculation of optical properties in weakly correlated systems.**Read More›** - Examples ›
**Principal Layer Green’s Functions**Many spintronic devices to emerge in recent years consist of spin transport through alternating, nanosized metallic layers**Read More›** - Examples ›
**Green’s Functions LMTO**A new concept for very fast electronic devices has emerged in recent years. Called JMRAM, it relies on the rotation of the phase of a Cooper pair wave function when it passes through a thin magnetic layer.**Read More›**