| Autor: |
Arham, H. Z., Hunt, C. R., Gillett, J., Das, S. D., Sebastian, S. E., Chung, D. Y., Kanatzidis, M. G., Greene, L. H. |
| Rok vydání: |
2013 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| Popis: |
We use point contact spectroscopy (PCS) to probe the superconducting properties of electron doped $\rm{Ba(Fe_{1-x}Co_x)_2As_2}$ ($\rm{x = 0.05, 0.055, 0.07, 0.08}$) and hole doped $\rm{Ba_{0.8}K_{0.2}Fe_2As_2}$. PCS directly probes the low energy density of states via Andreev reflection, revealing two distinct superconducting gaps in both compound families. Apart from the electron underdoped $\rm{Ba(Fe_{1-x}Co_{x})_2As_2}$, the excess current due to Andreev reflection for the compounds follows the typical BCS temperature dependence. For underdoped $\rm{Ba(Fe_{1-x}Co_{x})_2As_2}$, the temperature dependence of the excess current deviates from that of BCS, developing a tail at higher temperatures and surviving above bulk $T_c$. Possible explanations for this anomalous behavior are explored. |
| Databáze: |
arXiv |
| Externí odkaz: |
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