Bibliographic Details
| Title: |
Emerging superconductivity with broken time reversal symmetry inside a superconducting $s$-wave state |
| Authors: |
Grinenko, V., Sarkar, R., Kihou, K., Lee, C. H., Morozov, I., Aswartham, S., Büchner, B., Chekhonin, P., Skrotzki, W., Nenkov, K., Hühne, R., Nielsch, K., Efremov, D. V., Drechsler, S. -L., Vadimov, V. L., Silaev, M. A., Volkov, P., Eremin, I., Luetkens, H., Klauss, H. H. |
| Source: |
Nat. Phys. (2020) |
| Publication Year: |
2018 |
| Collection: |
Condensed Matter |
| Subject Terms: |
Condensed Matter - Superconductivity, Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons |
| More Details: |
In general, magnetism and superconductivity are antagonistic to each other. However, there are several families of superconductors, in which superconductivity may coexist with magnetism, and only a few examples are known, when superconductivity itself induces spontaneous magnetism. The most known compounds are Sr$_2$RuO$_4$ and some noncentrosymmetric superconductors. Here, we report the finding of a narrow dome of a novel $s+is'$ superconducting (SC) phase with broken time-reversal symmetry (BTRS) inside the broad $s$-wave SC region of the centrosymmetric multiband superconductor Ba$_{\rm 1-x}$K$_{\rm x}$Fe$_2$As$_2$ ($0.7 \lesssim x \lesssim 0.85$). We observe spontaneous magnetic fields inside this dome using the muon spin relaxation ($\mu$SR) technique. Furthermore, our detailed specific heat study reveals that the BTRS dome appears very close to a change in the topology of the Fermi surface (Lifshitz transition). With this, we experimentally demonstrate the emergence of a novel quantum state due to topological changes of the electronic system.
Comment: 28 pages, 11 figures |
| Document Type: |
Working Paper |
| DOI: |
10.1038/s41567-020-0886-9 |
| Access URL: |
http://arxiv.org/abs/1809.03610 |
| Accession Number: |
edsarx.1809.03610 |
| Database: |
arXiv |
