Anomalous Raman scattering from phonons and electrons of superconducting FeSe$_{0.82}$

Pradeep Kumar; Anil Kumar; Surajit Saha; D. V. S. Muthu; J. Prakash; S. Patnaik; U. V. Waghmare; A. K. Ganguli; A. K. Sood

doi:10.1016/j.ssc.2010.01.033

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arXiv · 1004.1612

Anomalous Raman scattering from phonons and electrons of superconducting FeSe$_{0.82}$

Pradeep Kumar·Anil Kumar·Surajit Saha·D. V. S. Muthu·J. Prakash·S. Patnaik·U. V. Waghmare·A. K. Ganguli·A. K. Sood

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Abstract

We report interesting anomalies in the temperature dependent Raman spectra of FeSe$_{0.82}$ measured from 3K to 300K in the spectral range from 60 to 1800 cm$^{-1}$ and determine their origin using complementary first-principles density functional calculations. A phonon mode near 100 cm$^{-1}$ exhibits a sharp increase by $\sim$ 5% in frequency below a temperature T$_s$ ($\sim$ 100 K) attributed to strong spin-phonon coupling and onset of short-range antiferromagnetic order. In addition, two high frequency modes are observed at 1350 cm$^{-1}$ and 1600 cm$^{-1}$, attributed to electronic Raman scattering from ($x^2-y^2$)to $xz$ / $yz$ $d$-orbitals of Fe.

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Pradeep Kumar, Anil Kumar, Surajit Saha, D. V. S. Muthu, J. Prakash, S. Patnaik, U. V. Waghmare, A. K. Ganguli, A. K. Sood. 2010-04-09. Anomalous Raman scattering from phonons and electrons of superconducting FeSe$_{0.82}$. https://doi.org/10.1016/j.ssc.2010.01.033

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