Initial objectives Employ plasmonic and geometrical resonances to enhance magneto-optical effects Investigate layouts for efficient rotation of polarization Magnetically tunable lens based on a gradient metasurface 1 Vitaliy Goryashko STINT meeting
Double-convex lens 1 + 1 = 1 𝑔 𝑨 1 𝑨 2 1 1 − 1 𝑔 = 𝑜 − 1 𝑆 1 𝑆 2 2 Vitaliy Goryashko STINT meeting
Transmission of a Gaussian beam through a lens ? Gaussian beam Lens 𝑙𝜍 2 The effect of the lens is an additional phase factor − 2𝑔 . The beam width just before and after the lens is the same. 3 Vitaliy Goryashko STINT meeting
Transmission of a Gaussian beam through a lens: NO PANIC! Here 𝑨 0 ≡ 𝑨 𝑆 After a lens the total phase reads 𝑙𝑨 + 𝑙𝜍 2 2𝑆 + 𝜔 − 𝑙𝜍 2 2𝑔 ⇒ 𝑙𝑨 + 𝑙𝜍 2 𝑆 ′ = 1 1 𝑆 + 1 2𝑆 ′ + 𝜔 𝑔 ′ new width 𝑋 𝑋 ′ = 𝑋 0 new focus 𝑨′ 𝑆 ⇒ 𝑆′ new Rayleigh 𝑨 0 ′ 4 Vitaliy Goryashko STINT meeting
Beam shaping A lens at the beam waist 𝑋 ′ = 0 𝑋 0 1 + 𝑨 0 /𝑔 2 𝑔 𝑨 ′ = 1 + 𝑔/𝑨 0 2 Focusing of a collimated beam 𝜇 ′ ≈ 𝑋 𝑔 = 𝜄 0 𝑔 0 𝜌𝑋 0 𝑨 ′ ≈ 𝑔 ′ ≈ 4 𝑀 = 𝑔 2𝑋 𝜌 𝜇𝐺 𝑀 ; 𝐺 𝐸 0 5 Vitaliy Goryashko STINT meeting
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