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تسجيل مستخدم جديدFlux free growth of large FeSe1/2Te1/2 superconducting single crystals by an easy high temperature melt and slow cooling method
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We report successful growth of flux free large single crystals of superconducting FeSe1/2Te1/2 with typical dimensions of up to few cm. The AC and DC magnetic measurements revealed the superconducting transition temperature (Tc) value of around 11.5K and the iso-thermal MH showed typical type-II superconducting behavior. The lower critical field being estimated by measuring the low field iso-thermal magnetization in superconducting regime is found to be above 200 Oe at 0K.
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We report flux free growth of superconducting FeSe single crystals by an easy and versatile high temperature melt and slow cooling method for first time. The room temperature XRD on the surface of the piece of such obtained crystals showed single 101
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ectron microscopy) results showed that the crystals are formed in slab like morphology and are near (slight deficiency of Te) stoichiometric with homogenous distribution of Fe and Te. The coupled structural and magnetic phase transition is seen at around 70K in both electrical resistivity and magnetization measurements, which is hysteric (deltaT = 5K) in nature with cooling and warming cycles. Magnetic susceptibility (chi-T) measurements showed the magnetic transition to be of antiferromagnetic nature, which is substantiated by isothermal magnetization (M-H) plots as well. The temperature dependent electrical resistivity measured in 10kOe field in both in plane and out of plane field directions showed that the hysteric width nearly becomes double to deltaT = 10K, and is maximum for the out of plane field direction for the studied FeTe single crystal. We also obtained a sharp spike like peak in heat capacity Cp(T) measurement due to the coupled structural and magnetic order phase transitions.
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