Scaling of the Fano effect of the in-plane Fe-As phonon and the superconducting critical temperature in ${\mathrm{Ba}}_{1\ensuremath{-}x}{\mathrm{K}}_{x}{\mathrm{Fe}}_{2}{\mathrm{As}}_{2}$
- Xu, Bing University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
- Cappelluti, E. Istituto di Struttura della Materia, Trieste, Italy
- Benfatto, Larra ISC-CNR and Department of Physics, Sapienza University of Rome, Italy
- Mallett, Benjamin P. P. University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland - The Photon Factory, Department of Physics, University of Auckland, New Zealand
- Marsik, Premysl University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
- Sheveleva, Evgeniia University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
- Lyzwa, Fryderyk University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
- Wolf, Thomas Institute of Solid State Physics, Karlsruhe Institute of Technology, Germany
- Yang, Rui Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- Qiu, X. G. Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- Dai, Y. M. National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, China
- Wen, H. H. National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, China
- Lobo, R. P. S. M. LPEM, ESPCI Paris, PSL University, CNRS, Paris, France - Sorbonne Université, CNRS, LPEM, Paris, France
- Bernhard, Christian University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
-
29.05.2019
Published in:
- Physical Review Letters. - 2019, vol. 122, no. 21, p. 217002
English
By means of infrared spectroscopy, we determine the temperature-doping phase diagram of the Fano effect for the in-plane Fe-As stretching mode in Ba1−xKxFe2As2. The Fano parameter 1=q2, which is a measure of the phonon coupling to the electronic particle-hole continuum, shows a remarkable sensitivity to the magnetic and structural orderings at low temperatures. Most strikingly, at elevated temperatures in the paramagnetic tetragonal state we observe a linear correlation between 1=q2 and the superconducting critical temperature Tc. Based on theoretical calculations and symmetry considerations, we identify the relevant interband transitions that are coupled to the Fe-As mode. In particular, we show that a sizable xy orbital component at the Fermi level is fundamental for the Fano effect and, thus, possibly also for the superconducting pairing.
- Faculty
- Faculté des sciences et de médecine
- Department
- Département de Physique
- Language
-
- English
- Classification
- Physics
- License
- License undefined
- Identifiers
-
- RERO DOC 326786
- DOI 10.1103/PhysRevLett.122.217002
- Persistent URL
- https://folia.unifr.ch/unifr/documents/307997
Other files
Statistics
Document views: 40
File downloads:
- ber_sfe.pdf: 39
- ber_sfe_sm.pdf: 28