A Mach-Zehnder interferometer is used as an optical intensity modulator. The two arms of the MZI have equal length L. In each arm we insert an electro-optic sample of length Ls, whose refractive index n, depends on the applied voltage Vacross the sample according to ns = no + nV, where no = 3 and n = 104 V- (a) Derive an expression for the normalized transmitted intensity T - Iour/lin of the MZI as a function of the applied voltage difference AV=V - V between the two arms. (b) Determine and plot the output intensity signal Tour(t) for the applied differential voltage signal AV(t) shown below. The electro-optic sample length is Ls = 1 mm, the input light has wavelength = 1.5 m and intensity Iin= 1 W/mm. Iin 16 Hli TIF Ls SY V Lout 11.25 V 1 15 V 2 3 7.5 V 4 t (ns)