Full-bandwidth anisotropic Migdal-Eliashberg theory and its application to superhydrides
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2023
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866909075420217344 |
|---|---|
| author | Lucrezi, Roman Ferreira, Pedro P. Hajinazar, Samad Mori, Hitoshi Paudyal, Hari Margine, Elena R. Heil, Christoph |
| author_facet | Lucrezi, Roman Ferreira, Pedro P. Hajinazar, Samad Mori, Hitoshi Paudyal, Hari Margine, Elena R. Heil, Christoph |
| contents | Migdal-Eliashberg theory is one of the state-of-the-art methods for describing conventional superconductors from first principles. However, widely used implementations assume a constant density of states around the Fermi level, which hinders a proper description of materials with distinct features in its vicinity. Here, we present an implementation of the Migdal-Eliashberg theory within the EPW code that considers the full electronic structure and accommodates scattering processes beyond the Fermi surface. To significantly reduce computational costs, we introduce a non-uniform sampling scheme along the imaginary axis. We demonstrate the power of our implementation by applying it to the sodalite-like clathrates YH$_6$ and CaH$_6$, and to the covalently-bonded H$_3$S and D$_3$S. Furthermore, we investigate the effect of maximizing the density of states at the Fermi level in doped H$_3$S and BaSiH$_8$ within the full-bandwidth treatment compared to the constant-density-of-states approximation. Our findings highlight the importance of this advanced treatment in such complex materials. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2310_00056 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Full-bandwidth anisotropic Migdal-Eliashberg theory and its application to superhydrides Lucrezi, Roman Ferreira, Pedro P. Hajinazar, Samad Mori, Hitoshi Paudyal, Hari Margine, Elena R. Heil, Christoph Superconductivity Materials Science Migdal-Eliashberg theory is one of the state-of-the-art methods for describing conventional superconductors from first principles. However, widely used implementations assume a constant density of states around the Fermi level, which hinders a proper description of materials with distinct features in its vicinity. Here, we present an implementation of the Migdal-Eliashberg theory within the EPW code that considers the full electronic structure and accommodates scattering processes beyond the Fermi surface. To significantly reduce computational costs, we introduce a non-uniform sampling scheme along the imaginary axis. We demonstrate the power of our implementation by applying it to the sodalite-like clathrates YH$_6$ and CaH$_6$, and to the covalently-bonded H$_3$S and D$_3$S. Furthermore, we investigate the effect of maximizing the density of states at the Fermi level in doped H$_3$S and BaSiH$_8$ within the full-bandwidth treatment compared to the constant-density-of-states approximation. Our findings highlight the importance of this advanced treatment in such complex materials. |
| title | Full-bandwidth anisotropic Migdal-Eliashberg theory and its application to superhydrides |
| topic | Superconductivity Materials Science |
| url | https://arxiv.org/abs/2310.00056 |