Adding dzyaloshinskii-moriya interaction

[MRM]

Hi,

Thanks for your useful software. How we can add dzyaloshinskii-moriya interaction?

Is there any command for these type of interaction?

 

[richard....@gmail.com]

Hi,

At the moment the only way to include the DM interaction is using the user defined unit cell with tensorial exchange interactions (Jxx, Jxy ... Jzz). There is a plan to include the DM interaction in a more generic form soon however - let me know if this is something that would be useful.

Richard

[MRM]

Thanks for your reply. Can you please explain a little bit more on how to include it because what you said I couldn't find in the manual.

Thanks a lot!

Massoud 

[richard....@gmail.com]

Hi Massoud,

Yes, at the moment this is a not well publicized feature, as it requires a reasonable understanding of coding to get it right. I have attached a draft of the file format required to generate your own unit cell, and a sample file for a simple cubic system. There is also a code sample in the vampire source code which can be used to generate this for the FCC crystal structure, and can be used as a basis for other crystal structures. The relevant part for the DM interaction is the exchange energies can be specified as isotropic (scalar), vector or tensor. For the tensor form you can include the DM interaction in the off-diagonal terms.

Eventually I would like to develop this as a proper tool, taking in a predefined unit cell and applying an exchange interaction based on some predefined values or Jij(r) function. However, this would require a few detailed tutorials to cover all the bases. Anyway, hopefully the attached is enough to get you on the way.

Richard

[MRM]

Thanks a lot!