4 GLYPH<s49>GLYPH<s46>GLYPH<s48> GLYPH<s48>GLYPH<s46>GLYPH<s56> GLYPH<s48>GLYPH<s46>GLYPH<s54> GLYPH<s48>GLYPH<s46>GLYPH<s52> GLYPH<s48>GLYPH<s46>GLYPH<s50> GLYPH<s48>GLYPH<s46>GLYPH<s48> GLYPH<s115> GLYPH<s40>GLYPH<s84>GLYPH<s41>GLYPH<s32>GLYPH<s61>GLYPH<s32> GLYPH<s40>GLYPH<s84>GLYPH<s41> GLYPH<s49>GLYPH<s46>GLYPH<s48> GLYPH<s48>GLYPH<s46>GLYPH<s56> GLYPH<s48>GLYPH<s46>GLYPH<s54> GLYPH<s48>GLYPH<s46>GLYPH<s52> GLYPH<s48>GLYPH<s46>GLYPH<s50> GLYPH<s48>GLYPH<s46>GLYPH<s48> GLYPH<s50>GLYPH<s46>GLYPH<s48> GLYPH<s49>GLYPH<s46>GLYPH<s53> GLYPH<s49>GLYPH<s46>GLYPH<s48> GLYPH<s48>GLYPH<s46>GLYPH<s53> GLYPH<s48>GLYPH<s46>GLYPH<s48> GLYPH<s32>GLYPH<s40>GLYPH<s84>GLYPH<s47>GLYPH<s84> GLYPH<s99> GLYPH<s41> GLYPH<s49>GLYPH<s46>GLYPH<s48> GLYPH<s48>GLYPH<s46>GLYPH<s56> GLYPH<s48>GLYPH<s46>GLYPH<s54> GLYPH<s48>GLYPH<s46>GLYPH<s52> GLYPH<s48>GLYPH<s46>GLYPH<s50> GLYPH<s48>GLYPH<s46>GLYPH<s48> GLYPH<s84>GLYPH<s32>GLYPH<s47>GLYPH<s32>GLYPH<s84>$_{GLYPH<s99>}$ GLYPH<s32>GLYPH<s102>GLYPH<s117>GLYPH<s108>GLYPH<s108>GLYPH<s32>GLYPH<s114>GLYPH<s97>GLYPH<s110>GLYPH<s103>GLYPH<s101>GLYPH<s32>GLYPH<s102>GLYPH<s105>GLYPH<s116> GLYPH<s32>GLYPH<s102>GLYPH<s105>GLYPH<s116>GLYPH<s32>GLYPH<s102>GLYPH<s114>GLYPH<s111>GLYPH<s109>GLYPH<s32>GLYPH<s48>GLYPH<s46>GLYPH<s52>GLYPH<s53> GLYPH<s32>GLYPH<s101>GLYPH<s120>GLYPH<s112>GLYPH<s101>GLYPH<s114>GLYPH<s105>GLYPH<s109>GLYPH<s101>GLYPH<s110>GLYPH<s116>GLYPH<s97>GLYPH<s108> GLYPH<s32>GLYPH<s102>GLYPH<s117>GLYPH<s108>GLYPH<s108>GLYPH<s32>GLYPH<s114>GLYPH<s97>GLYPH<s110>GLYPH<s103>GLYPH<s101>GLYPH<s32>GLYPH<s102>GLYPH<s105>GLYPH<s116> GLYPH<s32>GLYPH<s102>GLYPH<s105>GLYPH<s116>GLYPH<s32>GLYPH<s102>GLYPH<s114>GLYPH<s111>GLYPH<s109>GLYPH<s32>GLYPH<s116>GLYPH<s32>GLYPH<s61>GLYPH<s32>GLYPH<s48>GLYPH<s46>GLYPH<s52>GLYPH<s53> FIG. 5: (Color online) Superfluid density ρ s ( T /T c ) for Fe(Te,Se)#2 calculated with experimental Δ λ ( T ) and λ (0) = 560 nm. The solid (red) line is a fit the two-gap γ − model from 0 . 45 T c to T c . The dashed (blue) line is the fit over the full temperature range. Inset: temperature dependent super- conducting gaps calculated self-consistently during the fitting. the fitting are shown in the inset to Fig. 5. While the fitted positive curvature and reasonable coupling param- eters indicate a multi-gap nature of superconductivity in ”11” iron-chalcogenide superconductors, the failure at low temperatures and apparently non-exponential behav- ior requires extension to the anisotropic gap and inclusion effects of (possibly strong) pairbreaking [22]. In conclusion, a robust power-law behavior of the low-temperature λ ( T ) is found in single crys- tals of Fe$_{1}$$_{.}$$_{03}$(Te$_{0}$$_{.}$$_{63}$Se$_{0}$$_{.}$$_{37}$) and Fe$_{1}$$_{.}$$_{06}$(Te$_{0}$$_{.}$$_{88}$S$_{0}$$_{.}$$_{14}$) with Δ λ ( T ) ∝ T n with n ≈ 2 . 1 and ≈ 1 . 8, respectively. 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