Marion Nanosystems - Atomistix Toolkit

Atomistix Toolkit®

Atomic-scale modeling by first principles.

Atomistix ToolKit (ATK) is designed to help you understand and improve the functionality of nanoscale systems. The modeling platform can be used to calculate electrical properties of nanostructures coupled to semi-infinite electrodes under a finite bias voltage (so-called two-probe systems). Typical systems include

§ Tunnel junctions and interfaces (e.g. magnetic memory devices)

§ Molecules and nanotubes coupled to metal surfaces

§ A molecule inserted in a linear atomic wire

In addition, Atomistix ToolKit can be used for conventional electronic structure simulations, including spin-polarized calculations and optimized atomic geometries, of periodic and isolated systems.

Understanding the behavior of nanoscale devices is not trivial. A single atom out of place may dramatically improve, or destroy, the device functionality in ways that experiments cannot predict.

This is where modeling enters. Analyzing the atomic-scale properties by computer simulations makes it possible to limit and to tailor the experiments needed to develop a working device. Since physical experiments, especially at the nanoscale, are associated with considerable costs, Atomistix ToolKit provides an effective way to do business.

Atomistix ToolKit can:

Model

§ heterogeneous two-probe systems (nanostructures coupled to semi-infinite

electrodes)

§ periodic systems (bulk crystals and nanotubes)

§ molecules

Calculate

§ Transport properties

§ transmission coefficients and transmission spectra under an applied bias voltage

§ transmission eigenvalues and eigenchannels

§ electrical current through a two-probe system

§ density of states and local density of states

§ voltage drop across a two-probe system

§ spin polarization

§ and much more …

§ Electronic properties

§ energy bands and Bloch functions

§ molecular eigenenergies and orbitals

§ electron densities and effective potentials

§ spin polarization

§ and much more …

§ Optimized atomic geometries

§ quasi-Newton relaxation

§ molecular dynamics minimization/steepest descent method

A detailed list of features in ATK can be found here.

A combination of density functional theory (DFT) and non-equilibrium Green's function methods makes Atomistix ToolKit an efficient and powerful tool for calculating and understanding intrinsic properties of nanoscale systems.

Atomistix ToolKit is a further development of the TranSIESTA method. A list of scientific publications where Atomistix ToolKit (or its precessor TranSIESTA-C) has been used is available upon request. Please contact us for a non-comprehensive list.

NanoLanguage scripting

Atomistix ToolKit is a script-based application that uses the Python-based NanoLanguage. NanoLanguage offers

§ Flexibility and control

§ Transparency

§ Extendable functionality by user-defined functions

NanoLanguage is an ideal tool for automating series of simulations where geometric, material, or other parameters are to be optimized.

Atomistix ToolKit can also be used interactively, and then behaves like IPython. The interactive mode is particularly suitable for analysis of the calculated results.