Raman spectroscopy and normal state electric transport in Fe(Se1􀀀xTex) super- conductors

L. LANOËL; G. BRIDOUX; M. VILLAFUERTE; M. L. AMIGÓ; M. V. ALE CRIVILLERO; D. G. FRANCO; G. NIEVA

Simposio; XXIII Simposio Latinoamericano de Física del estado Sólido; 2018

We present a Raman spectroscopy study ofFe(Se1􀀀xTex) single crystals prepared at high (850C) and low (400C) temperatures. The high temperature synthesis results in samples with two phases, the superconducting b-FeSe and the magnetic Fe7Se8 while the low temperature treatment yield only -FeSe phase crystals. The Te substitution was observed to change the magnetic phase content in high temperature synthetized samples[1]. We found peaks at 235 cm􀀀1 and 253 cm􀀀1, that are attributed to iron vibrational modes, only in the single phase samples. Electrical transport in the normal state show clearly the tetragonal-orthorrombic transition at 90K in the low temperature grown crystals and strain related anomaliesfrom 90 to 220K.