Fig. 5
Profile of the graded index Pt layer in the samples t1, t2, t3, and t4 and depth dependent optical constants of those sample at 300 nm, 600 nm, and 900 nm. (a) Composition profile of graded index Pt layer vs. position in the graded index layer modelled using SE for sample t1, t2, t3 and t4. The position in the graded index Pt layer is normalized with respect to the thickness of the graded index Pt layer tp (Table 1). Refractive index n (solid line) and absorption index k (scattered line) at 300 nm (brown), 600 nm (green), and 900 nm (violet), across the (b) NiCr/Ti/Pt constant index/Pt graded index/void part of sample t4 and (c, f) across the Ti/Pt constant index/Pt graded index/Void part of samples t3 and t4. (d, e) Ti/ Pt graded index/Void part of samples t1 and t2. Position of interfaces NiCr/Ti (I), Ti/Constant index layer (II) and Ti/Graded index layer (V), Constant index/Graded index (III), and Graded index/Void (IV) is labeled with Roman numbers. Total length of x-axis is (b) and (c–f) 5 nm thick Ti layer is completely represented. Total length of x-axis in (b) is 155 nm and (c–f) is 55 nm. MSE for fitted samples NiCr, NiCr/Ti, t1, t2, t3 and t4 are 0.078, 0.177, 0.676, 0.625, 0.772 and 0.801, respectively.
