Enhanced physical properties of single crystal Fe0.99Te0.63Se0.37 prepared by self-flux synthesis method


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Onar K. , Oezcelik B., GULER N. K. , OKAZAKI H., TAKEYA H., TAKANO Y., et al.

JOURNAL OF ALLOYS AND COMPOUNDS, cilt.683, ss.164-170, 2016 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 683
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1016/j.jallcom.2016.05.086
  • Dergi Adı: JOURNAL OF ALLOYS AND COMPOUNDS
  • Sayfa Sayısı: ss.164-170

Özet

In this study, we have systemically studied the physical, electrical and magnetic properties of Fe0.99Te0.63Se0.37 single crystalline samples prepared by self-flux method. We found that the self-flux method is a suitable synthesis technique for this alloys if setting of experimental parameters made carefully. The M-H curve affirms that samples are typical type-II superconductor. Strong sign of bulk superconductivity, even after high field measurements, were seen. Calculated J(c)(mag) values, at zero field, were found to be 7.7 x 10(5) Acm(-2) and 2.6 x 10(4) Acm(-2) for 5 K and 10 K respectively. The upper critical field H-c2(0) has been determined with the magnetic field parallel to the sample surface and yielding a maximum value of 65 T. At the zero field coherence length, xi, value was calculated to be 2.24 nm for 10% T-c(offset) which is significantly larger (approximately 6 fold) than the unit cell, a, and indicating the absence of weak link behavior in the sample. Calculated mu H-0(c2)(0)/k(B)T(c) rate indicated comparably higher value (3.66 T/K) than the Pauli limit (1.84 T/K) and obtained results were suggested unconventional nature of superconductivity in our samples. (C) 2016 Elsevier B.V. All rights reserved.

In this study, we have systemically studied the physical, electrical and magnetic properties of Fe0.99Te0.63Se0.37 single crystalline samples prepared by self-flux method. We found that the self-flux method is a suitable synthesis technique for this alloys if setting of experimental parameters made carefully. The M-H curve affirms that samples are typical type-II superconductor. Strong sign of bulk superconductivity, even after high field measurements, were seen. Calculated Jc mag values, at zero field,
were found to be 7.7  105 Acm2 and 2.6  104 Acm2 for 5 K and 10 K respectively. The upper critical field Hc2(0) has been determined with the magnetic field parallel to the sample surface and yielding a maximum value of 65 T. At the zero field coherence length, x, value was calculated to be 2.24 nm for 10% Tcoffset which is significantly larger (approximately 6 fold) than the unit cell, a, and indicating the absence
of weak link behavior in the sample. Calculated m0Hc2(0)/kBTc rate indicated comparably higher value (3.66 T/K) than the Pauli limit (1.84 T/K) and obtained results were suggested unconventional nature of superconductivity in our samples.