Optical properties for superconducting parent compound Ca₁₀(Pt₄As₈)(Fe₁₀As₁₀) single crystal.

We have measured the reflectivity of the parent compound Ca₁₀(Pt₄As₈)(Fe₁₀As₁₀) single crystal (T_c =32.6 K) over the broad frequency range from 20 cm⁻¹ to 12000 cm⁻¹ and for temperatures from 8 K to 300 K. The optical conductivity spectra of the low frequency region (< 1000 cm⁻¹) in the normal state (38 K T 300 K) is well fitted with two Drude forms, which indicates the presence of multiple bands at the Fermi level. When the superconducting state in 8 K, the real part optical conductivity ₁ was not completely suppressed. This indicates that the superconducting gap of this compound is not fully open in Fermi surface. So we can think about the possibility of a nodal point in the superconducting gap of this compound. The extracted SC gap size is = 2.85 meV and the scattering rate 1/= 34.71 meV, suggesting Ca₁₀(Pt₄As₈)(Fe₁₀As₁₀) as a single-gap superconductor with a nodal point possibility in superconducting gap.