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@GPMueller GPMueller released this 23 Jun 20:36
· 531 commits to master since this release
v2.0.0
24a84ff

Note that the paper about this code has been published and should be cited when using the code for scientific publications: Phys. Rev. B 99, 224414 (2019) (arxiv version: arXiv:1901.11350).

Added Features

Minimum Mode Following (MMF)

See the method paper, Phys. Rev. Lett. 121, 197202 (2018), for more details.

This method can be used to search out saddle points in the energy landscape.
See the docs for the available parameters.

Harmonic Transition State Theory (HTST)

See the method paper, Comp. Phys. Comm. 196, 335 (2015), for more details.

This method can be used to estimate the rate of thermally activated transitions in a spin system
from the critical points in the energy landscape corresponding to a given transition. It can
therefore be used to estimate lifetimes of (meta-) stable spin configurations.
See the docs for the available parameters.

Diplolar interactions

Also referred to as dipole-dipole interaction (DDI), stray field or demagnetising field.
See the docs for the available parameters.

Impvroved spring forces for GNEB

Spring force ratio

This is the ratio of weighting of the energy difference and the geodesic distance
between images in the calculation of the spring force. A ratio of 0.5 will cause the lengths
of the interpolated energy polynomials between image to take equal lengths.

Path shortening force

The path shortening force tries to reduce the geodesic length of the GNEB transition.
It can be used to pre-converge a path, avoiding the effect of zero energy modes, which
might otherwise hinder convergence.

If it is set to a large value, the path will tend to the homogeneous interpolation between
bounding images.

4th order Runge-Kutta solver

This solver is more precise for dynamical simulations than the other solvers, such as
Heun's (2nd order RK), but requires more calculations of the energy gradient.

Desktop GUI changes

  • added configurations-like for setting atom types / defects
  • added new "interactive mode" for setting atom types / defects
  • improved InfoWidget
  • improvements for multi-atom basis cells
  • added colormap cardinal axis
  • fixed some locale bugs

Interface Changes

Input File

There are some breaking changes to the input file!

C API

  • Added APIs for MMF and HTST
  • Made the function naming more consistent
  • Split Simulation_Start API into one function per Method
  • Added APIs for setting atom types / defects and pinning
  • Added Chain_Set_Length
  • Added APIs for GNEB image types and spring force parameters

Python API

Renamed and/or recapitalised all APIs in order to adhere closer to
PEP8.
The capitalisation should now consistent.

Bugfixes

  • fixed the OVF output writing (both header and binary endianness)
  • fixed several build problems, such as
    • the default build type
    • passing CMake options from the top level to the Spirit core library
    • building the CUDA backend on Windows
  • several fixes for multi-atom basis cells
  • corrected stochastic thermal field in LLG method
  • minor fix to homogeneous transition function
  • corrected calculation of topological charge
  • minor fix of isosurfaces for multi-atom basis cells
  • bugfix for geometry dimensionality calculation
  • several fixes for resizing the geometry at runtime
  • fixed spin spiral creation

Other Improvements

  • moved mu_s from Hamiltonian to Geometry
  • improved logging of backtraces and unhandled exceptions
  • added a Dockerfile
  • updated and completed C API docs and setup autogenerating Python API docs
  • added logos to docs
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