Determine how electron mobility changes with material composition, structure, and lattice symmetries.Choose between three different methods to calculate phonon-limited mobility: Boltzmann Transport Equation, Molecular Dynamics-Landauer and Special Thermal Displacement-Landauer methods, depending on the size and the type of your system.
In QuantumATK we strive to make this type of calculations easily accessible, accurate, fast, and able to handle large systems. Including such effects, in particular for amorphous materials, systems with low lattice symmetry, nanostructures and devices is very complex. In order to calculate mobility accurately, multiple effects must all be considered: electron-phonon interactions (i.e., electron scattering due to interactions with the vibrations of the lattice), surface effects, strain, and the dimensions and shapes of the material on the nanoscale. Conveniently resolve different phonon contributions to optical propertiesĮlectron mobility is an important performance indicator of materials however, it is very challenging to model at the atomic scale.Simulate optical spectrum including a possibility to calculate the intraband contribution for metals.Obtain refractive indices, extinction coefficients, reflectivity, susceptibility, optical conductivity.Simulate Raman spectrum: either polarization dependent for one or multiple angles between incoming and scattered light, or polarization averaged spectrum.including ionic contribution to optical properties, and including temperature dependencies through electron-phonon coupling. Furthermore, QuantumATK stands out for offering advanced features for polar materials, i.e. The fully automated workflows in NanoLab GUI, from initial relaxation to calculation of advanced spectroscopic properties, highly reduce the chance of errors and turnaround time (TAT). QuantumATK enables simulation and advanced analysis of an exceptionally large range of optical and electro-optical parameters. Optic and electro-optical analysis tools are of paramount importance when characterizing emerging bulk, 2D materials and nanostructures, extracting information about vibrational, and chemical properties, inhomogeneities, strain, crystallinity, electron-phonon coupling and anharmonicities in a local environment, and detecting different structural phases. Predict reaction mechanisms (transition states, reaction pathways, and reaction barriers) using the nudged elastic band (NEB) method with and without an electric field.Examine how defect formation energies and thermodynamic transition levels depend on the type of defect (vacancy, substitutional, interstitial), charge state and supercell repetition.Investigate how band structure, DOS and their projections, molecular spectrum, Fermi surfaces, exchange coupling constants, spin life time, magnetic anisotropy energy, and many more electronic properties change with material composition and structure.
band structure and DOS, turn a 2D plot into a Python script, which can be modified or batch-processed. It is also very easy to plot projections of band structure and density of states (DOS) onto atoms, spin, orbitals, or angular momenta, in any desired combination, combine plots, e.g. This makes it possible to shift seamlessly from LCAO to Plane-Wave basis sets, and, thus, easily adjust and test tradeoffs between speed and accuracy.
Being fully integrated into the QuantumATK NanoLab environment, QuantumATK DFT-PlaneWave code is probably the most flexible and user friendly plane-wave code available. QuantumATK is the only code including pseudopotential-based density functional theory (DFT) methods with LCAO and plane-wave basis sets in one framework. Completeness of methods, ease-of-use and advanced post-processing capabilities make QuantumATK superior to other tools for calculation of electronic properties. Nanoscale dimensions and increasing complexity of materials render its experimental characterization challenging and thus there is a need for atomic-level modeling to complement experimental characterization of electronic properties.