Gaussian beam formulae for Q2. Beam waist: W = (20) /2, Beam radius: W(z) = W...

  

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Gaussian beam formulae for Q2. Beam waist: W₁ = (20) ¹/2, Beam radius: W(z) = W₁ [1 + (-)²]¹¹². 2zo1/2 Wo ²[1 + (²²9)²], Phase retardation: 3 = arctan (2²) Radius of curvature: R(z) = z 1+ Optical fluence (in J.m2) F(p) = 2ET 24/7 exp[-2 (+)²]. Q 2(c) Show that at large z, 00 ~ 2 лWo [5 Marks] and estimate the value half-beam divergence angle o for Wo = 20 mm (with = 10.6 μm). Also, calculate the beam radius at z = 2zo, z = 4zo and z = 8zo. Gaussian beam formulae for Q2. Beam waist: W₁ = (20) ¹/2, Beam radius: W(z) = W₁ [1 + (-)²]¹¹². 2zo1/2 Wo ²[1 + (²²9)²], Phase retardation: 3 = arctan (2²) Radius of curvature: R(z) = z 1+ Optical fluence (in J.m2) F(p) = 2ET 24/7 exp[-2 (+)²]. Q 2(c) Show that at large z, 00 ~ 2 лWo [5 Marks] and estimate the value half-beam divergence angle o for Wo = 20 mm (with = 10.6 μm). Also, calculate the beam radius at z = 2zo, z = 4zo and z = 8zo.