Fig. 1. (a) Temperature dependent R of Ca_0.73La_0.27(Fe_0.96 Co_0.04)As₂. (b) Temperature T dependent normalized magnetization data for H = 10 Oe under both zero-field-cooled (ZFC) and field cooled (FC) conditions.

Fig. 2. (a) Typical angular θ dependent torque τ at T = 300 K with a magnetic field H = 5 T, 6 T, 7 T, 8 T, 9 T. The solid lines are fits of the data with τ = τ₀ sin2θ. Inset: sketch of the single crystal with the orientation of the magnetic field H with respect to the crystallographic axes. (b) The torque coefficient τ₀ vs. H² at T = 25 K and 300 K. The solid lines are linear fit of the data.

Fig. 3. (a) Angle θ dependence of the torque τ measured in increasing (green) and decreasing (red) angle at T = 17 K and H = 3 T, and the reversible torque τ_rev (blue). (b) τ_rev vs. θ for H = 3 T, 4 T, 5 T, 6 T, 7 T, 8 T, 9 T. The solid lines are fitting curves by Eq. (5). (c) The magnetic field H dependence of anisotropy parameter γ. (d) H dependence of the fitting parameter β. The solid line is a guide to the eyes.

Fig. 4. (a) The reversible part of the torque data τ_rev for T = 15 K, 16 K, 17 K,18 K with H = 9 T. The solid lines are fitting curves by Eq. (5). (b) The reduced temperature t (T/T_c) dependence of the anisotropy parameter γ. The squares represent data obtained from our torque measurements. The blue triangles represent data of Ca_0.82La_0.18FeAs₂,^[11] others symbols represent data for Ca_0.8La_0.2(Fe_0.98Co_0.02)As₂^[12] and Ca_0.8La_0.2(Fe_0.98Co_0.02)As₂,^[30] respectively. The solid line is a guide to the eyes. (c) The reduced temperature t dependence of the in-plane penetration depth λ_ab. (d) The reduced temperature t dependence of the superfluid density n_s ∝ λ⁻² extracted from the torque data at H = 9 T. The dashed line is a guide to the eyes.