Segmented waveguide arrays: deriving discrete diffraction relations in a square lattice photonic crystal

Abstract

Segmented strip-loaded waveguide arrays are investigated within a rigorous square lattice photonic crystal model. We derive a full multiband discrete diffraction approach for near-axial injection in the direction of a lattice vector. We obtain an effective waveguide array picture, with quasi-linear dependence on the segmentation ratio in a simplified single-band scheme. Our results are validated by beam deviation experiments. Such a diffraction framework allows for efficient shaping of the phase map in waveguide arrays and enriches the engineering toolkit of photonic crystals with the in-plane free propagation structures of discrete photonics.

Discrete diffraction and Bloch oscillations in non-Hermitian frequency lattices induced by complex photonic gauge fields

“…Then, we analyze the frequency-energy refraction in two cascade modulators with modulation depths m ϕ , m ϕ and complex gauge potentials φ + iκ, φ + iκ . For cases (1) and (3) with φ = φ (or φ = φ ) and κ = κ , the output field is uniformly described by E out (t ) = a 0 e iω 0 t e im ϕ cos( t+φ+iκ ) e im ϕ cos( t+φ +iκ ) = a 0 e iω 0 t e i…”

“…Photonic lattice systems, such as photonic crystals, metamaterials, and coupled waveguide arrays, provide ideal platforms to emulate wave transport dynamics of electrons in solid-state systems [1][2][3][4][5]. Typical transport phenomena include the force-free discrete diffraction and force-driven Bloch oscillations [6][7][8][9][10][11].…”

Engineering of Zeno Dynamics in Integrated Photonics

“…Photonic lattices consisting of evanescently coupled waveguide arrays could be defined as appropriate configurations, in which the optical modes can be engineered along the transverse direction. Particularly, the periodically segmented waveguide is investigated both for a single waveguide [24,25] and in the array [26], which is used for image reconstruction [27], optical lens [28], and generating controllable loss [29]. Because of the analogy of the Schrödinger equation for quantum wave functions and the paraxial Helmholtz equation for classical electric fields, the temporal evolution of a quantum system is therefore equivalent to spatial propagation of guided light waves in waveguides [30,31].…”

“…1(a)], we use two continuous waveguides (labeled by WG1 and WG2) with mutual coupling representing a two-level system under monitoring. A periodically segmented waveguide [26,29] is appended to the left side of WG1 at d ¼ 5 μm, which leads to equivalently stroboscopic measurements on S. For each element of the noncontinuous waveguide, the waveguide segment has the length m, and the segment-to-segment gap is l − m. These segmented waveguides serve as the measurement apparatus M, which is coupled to S. In the gap, the coupling between M and S vanishes. The light dissipates from M, in which photons are emitted (Supplemental Material [42]).…”