EPW Forum

Dear EPW developers and users,

In EPW 5.8, the system_ 2D flag becomes available, but system_ 2D =. true. is invalid. In the manual, regarding the system_2D description is shown in the picture. If we study materials like graphene and MoS2, How to set up system_ 2D?

sincerly,
mxh

Dear mxh,

Thanks for your questions about the label "system_2d" of latest EPW version. We also have the same problem about it.

We sincerely hope that the problem can be resolved as soon as possible!

Best wishes,
LiuHD

Hi Liu and mxh,

The system_2D in EPW 5.8 has been implemented using multiple formalisms. As already mentioned in the description of the input variables, I am mentioning it here again, the dipole_sp option will perform 2D truncation using "https://journals.aps.org/prb/abstract/1 ... 107.155424" while dipole_sh will perform 2D truncation using "https://journals.aps.org/prb/abstract/1 ... 105.115414". Both of them should give similar result. While the 'quadrupole' tag will take into account quadrupolar interactions. However it requires the presence of a precalculated file "quadrupole.fmt".

Best,
Sabya.

Dear Sabya,

Thanks for your reply.

Other one question troubling me is whether the table can decrease the memory per pool when calculate the superconducting gaps at low temperatures?

Best regards,
LiuHD.

Dear Sabya,

Thanks a lot!

Best regards,
mxh