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Electromagnetic Black Hole Made of Metamaterials B96901128 王郁翔 Outline 1. Introduction 2. Theory & Structures 3. Experiments & Results 4. Conclusions 5. References What is Black Hole? 1. Laplace’s view 2. Schwarzschild’s solution of Einstein’s vacuum field equation (general relativity) Analogy Between Mechanics and Electromagnetic Curved space----inhomogeneous metamaterial Least action principle----Fermat’s principle Characteristics Non-resonant structure—broad band light absorption Omnidirectional Lossy core and lossless shell. Usage Cross-talk reduction Thermal light emitting source Solar light harvesting Theoretic Analysis Hamilton equations: p:generalized momentum q:generalized coordinate H: Hamiltonian Theoretic Analysis For cylindrical structure, use semiclassical analysis[3] Inhomogeneous permittivity— potential. different Inhomogeneous Permeability For n=-1, 1, 2, 3 Choose n=2 easiest to fabricate Structures Lossy circular inner core—ELC resonator (20 layers) Lossless circular shell—I-shaped metamaterials (40 layers) ELC resonator t=1.6mm,g=0.3mm,p=0.15mm,s=0.65mm Resonate at 18GHz I-shaped w=0.15mm, q=1.1mm, 18GHz Different m, different ε Experiment condition 18GHz Cell 1.8mm R=108mm, Rc=36mm, height=5.4mm Fabricate on styrofoam board Parallel-plate waveguide near-field scanning system to measure Simulation Gaussian beam Absorbing rate 99.94%, 98.72% Simulation & Experiment Narrow beam simulation, experiment Simulation of Plane wave Electric field and power flow. Simulation & Experiment Nearby source excitation. Optical Frequency R=20μm, Rc=8.4μm, λ=1.5 μm Conclusion Designed, fabricated, and measured an electromagnetic black hole. Really useful in solar light harvesting? Reference [1] Cheng,Q., Cui,T.J., Jiang,W.X., Cai,B.G. An electromagnetic black hole made of metamaterials, 2009 [2] Narimanov, E. E., Kildishev, A. V. Optical black hole: Broadband omnidirectional light absorber. Appl.Phys. Lett. 95, 041106 (2009). [3] Landau, L. D., & Lifshitz, E. M. The Classical Theory of Fields, 4th ed. (Butterworth Heinemann, 1999).