Raman Study of Cooper Pairing Instabilities in (Li_{1-x}Fe_{x})OHFeSe.
1Walther Meissner Institut, Bayerische Akademie der Wissenschaften, 85748 Garching, Germany.
Physical Review Letters
|December 4, 2020
Summary
We studied electronic Raman spectra of (Li_{1-x}Fe_{x})OHFeSe superconductors. Two collective modes were observed below the critical temperature (Tc), suggesting hybridized electron bands are key to superconductivity in these iron-based compounds.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Superconductivity
Background:
- Iron-based superconductors exhibit complex electronic properties.
- Understanding the pairing mechanism is crucial for advancing superconductivity research.
Purpose of the Study:
- Investigate the electronic Raman spectra of (Li_{1-x}Fe_{x})OHFeSe.
- Identify collective modes and their relation to superconductivity.
- Elucidate the pairing mechanism in iron-based superconductors.
Main Methods:
- Electronic Raman spectroscopy with varying light polarization and temperature.
- Analysis of spectral weight redistribution and peak characteristics.
- Comparison with single-particle spectroscopy and band structure calculations.
Main Results:
- Observed superconducting signatures in B_{1g} spectra, including spectral weight redistribution.
- Identified two distinct collective modes at 110 cm^{-1} and 190 cm^{-1} below T_{c}.
- Absence of gap features in A_{1g} and B_{2g} symmetries.
Conclusions:
- The findings suggest pairing between hybridized electron bands is a plausible mechanism.
- Demonstrates the proximity of pairing states in iron-based superconductors.
- Highlights the significant role of band structure effects in Fe-based compounds.
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