Fermi-Level Pinning of Yu-Shiba-Rusinov States in a Superconductor with Weakly Broken Spin-Rotational Invariance
Fuente:
arXiv
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866915316253065216 |
|---|---|
| author | Andriyakhina, E. S. Khortsev, S. L. Evers, F. |
| author_facet | Andriyakhina, E. S. Khortsev, S. L. Evers, F. |
| contents | As is well known, magnetic impurities adsorbed on superconductors, e.g. of the s-wave type, can introduce a bound gap-state (Yu-Shiba-Rusinov resonance). We here investigate within a minimal model how the impurity moment arranges with respect to a weak homogeneous internal magnetic field employing a fully self-consistent mean-field treatment. Our investigation reveals a critical window of impurity-to-substrate coupling constants, $J$. The width of the critical region, $δJ$, scales like $δJ \sim B/Δ$, where $B$ is the magnitude of the internal field, that breaks the spin-rotation symmetry, and $Δ$ is the bulk order parameter. While tuning $J$ through the window, the energy of the Yu-Shiba-Rusinov (YSR) resonance is pinned to the Fermi energy $\varepsilon_{\rm F}$ and the impurity moment rotates in a continuous fashion. We emphasize the pivotal role of self-consistency: In treatments ignoring self-consistency, the critical window adopts zero width, $δJ=0$; consequently, there is no pinning of the YSR-resonance to $\varepsilon_{\rm F}$, the impurity orientation jumps and therefore this orientation cannot be controlled continuously by fine-tuning the coupling $J$. In this sense, our study highlights the significance of self-consistency for understanding intricate magnetic interactions between superconductive materials and Shiba chains. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2405_20290 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Fermi-Level Pinning of Yu-Shiba-Rusinov States in a Superconductor with Weakly Broken Spin-Rotational Invariance Andriyakhina, E. S. Khortsev, S. L. Evers, F. Superconductivity As is well known, magnetic impurities adsorbed on superconductors, e.g. of the s-wave type, can introduce a bound gap-state (Yu-Shiba-Rusinov resonance). We here investigate within a minimal model how the impurity moment arranges with respect to a weak homogeneous internal magnetic field employing a fully self-consistent mean-field treatment. Our investigation reveals a critical window of impurity-to-substrate coupling constants, $J$. The width of the critical region, $δJ$, scales like $δJ \sim B/Δ$, where $B$ is the magnitude of the internal field, that breaks the spin-rotation symmetry, and $Δ$ is the bulk order parameter. While tuning $J$ through the window, the energy of the Yu-Shiba-Rusinov (YSR) resonance is pinned to the Fermi energy $\varepsilon_{\rm F}$ and the impurity moment rotates in a continuous fashion. We emphasize the pivotal role of self-consistency: In treatments ignoring self-consistency, the critical window adopts zero width, $δJ=0$; consequently, there is no pinning of the YSR-resonance to $\varepsilon_{\rm F}$, the impurity orientation jumps and therefore this orientation cannot be controlled continuously by fine-tuning the coupling $J$. In this sense, our study highlights the significance of self-consistency for understanding intricate magnetic interactions between superconductive materials and Shiba chains. |
| title | Fermi-Level Pinning of Yu-Shiba-Rusinov States in a Superconductor with Weakly Broken Spin-Rotational Invariance |
| topic | Superconductivity |
| url | https://arxiv.org/abs/2405.20290 |