| Autor: |
C, Martin, M E, Tillman, H, Kim, M A, Tanatar, S K, Kim, A, Kreyssig, R T, Gordon, M D, Vannette, S, Nandi, V G, Kogan, S L, Bud'ko, P C, Canfield, A I, Goldman, R, Prozorov |
| Rok vydání: |
2009 |
| Zdroj: |
Physical review letters. 102(24) |
| ISSN: |
0031-9007 |
| Popis: |
The superconducting penetration depth lambda(T) has been measured in RFeAsO(0.9)F(0.1) (R = La, Nd) single crystals (R-1111). In Nd-1111, we find an upturn in lambda(T) upon cooling and attribute it to the paramagnetism of the Nd ions, similar to the case of the electron-doped cuprate Nd-Ce-Cu-O. After the correction for paramagnetism, the London penetration depth variation is found to follow a power-law behavior, Deltalambda_{L}(T) proportional, variantT;{2} at low temperatures. The same T2 variation of lambda(T) was found in nonmagnetic La-1111 crystals. Analysis of the superfluid density and of penetration depth anisotropy over the full temperature range is consistent with two-gap superconductivity. Based on this and on our previous work, we conclude that both the RFeAsO (1111) and BaFe(2)As(2) (122) families of pnictide superconductors exhibit unconventional two-gap superconductivity. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
