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arXiv · 1010.2374

Phonon, Two-Magnon and Electronic Raman Scattering of Fe1+yTe1-xSex

K. Okazaki·S. Sugai·S. Niitaka·H. Takagi
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Abstract

We have measured Raman scattering spectra of single-crystalline FeTe0.6Se0.4 (T_c ~ 14.5 K) and its parent compound Fe1.074Te at various temperatures. In the parent compound Fe1.074Te, A1g and B1g modes have been observed at 157.5 and 202.3 cm-1, respectively, at 5 K. These frequencies qualitatively agree with the calculated results. Two-magnon excitation has been observed around 2300 cm-1 for both compounds. Temperature dependence between the electronic Raman spectra below and above T_c has been observed and 2Δand 2Δ/k_BT_C have been estimated as 5.0 meV and 4.0, respectively.

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K. Okazaki, S. Sugai, S. Niitaka, H. Takagi. 2010-12-09. Phonon, Two-Magnon and Electronic Raman Scattering of Fe1+yTe1-xSex. https://doi.org/10.1103/physrevb.83.035103

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