Artificial Sum Frequency Generation from Resonant Metasurface

The artificial sum frequency generation is generated from resonant graphene-gold metasurface without the insertion of nonlinear materials. By introducing both electric dipole resonance and magnetic resonance at two fundamental frequencies, the SFG efficiency is more than 2 orders of magnitude larger than that of second harmonic generation with only one resonance. The proposed concept will pave the way for establishing novel engineered nonlinear metamaterials and their practical applications.