2012/02/21 by N. Kumar, M. Botey, R. Herrero +2
Physics and Astronomy · #Angular spectrum method #Anisotropy #Brillouin zone #Harmonics #Nonlinear Photonic Systems #Photorefractive and Nonlinear Optics #Quantum Mechanics and Non-Hermitian Physics #Radiation #Square lattice #Symmetry (geometry) #Wave propagation #Wavelength #physics.comp-ph #physics.optics
paper · pdf · doi:10.1016/j.photonics.2012.06.003
arxiv created 2012/02/21 · openalex publication_date 2012/06/19 · arxiv updated 2015/06/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Amplification/attenuation of light waves in artificial materials with a gain/loss modulation on the wavelength scale can be sensitive to the propagation direction. We give a numerical proof of the high anisotropy of the gain/loss in two dimensional periodic structures with square and rhombic lattice symmetry by solving the full set of Maxwell's equations using the finite difference time domain method. Anisotropy of amplification/attenuation leads to the narrowing of the angular spectrum of propagating radiation with wavevectors close to the edges of the first Brillouin Zone. The effect provides a novel and useful method to filter out high spatial harmonics from noisy beams.