Optical device including waveguide grating structure

Abstract

Optical devices (100) including waveguide grating structures (102) are described. In accordance with one embodiment, an optical device (100) is provided comprising a horizontal waveguide grating structure (102) having at least one waveguiding layer (104) and at least one subwavelength periodic grating layer (106). The optical device (100) further comprises upper and lower cladding layers (108, 110) immediately adjoining respective upper and lower surfaces (209, 205) of the waveguide grating structure and having refractive indices lower than a lowest-index one of the waveguiding layers, incident radiation propagating (IN) through one of the upper and lower cladding layers (108, 110) toward the waveguide grating structure. The waveguide grating structure (102) is configured for peak reflection of the incident radiation at a peak reflection frequency. A cumulative thickness of the waveguiding layers (104) is less than one tenth of a free space wavelength of the incident radiation at the peak reflection frequency divided by an average refractive index of the waveguiding layers.

Description

technical field [0001] This patent specification relates to optical devices. More specifically, this patent specification relates to optical devices comprising waveguide grating structures for providing capabilities such as filtering and modulating incident optical signals. Background technique [0002] Devices for modifying the propagation of electromagnetic radiation, such as by filtering and modulation, represent fundamental building blocks of many technological endeavors. Filtering generally refers to selective processing, such as selective transmission or reflection, of electromagnetic radiation based on its frequency. Modulation generally refers to changing the properties of electromagnetic waves or signals in time, such as amplitude, frequency, phase, etc., according to time-varying control signals or modulation signals. Optical filtering and optical modulation refer to filtering and modulating, respectively, electromagnetic radiation at optical frequencies (which m...

AI Technical Summary

Problems solved by technology

[0005] More generally, practical problems often arise when implementing at least one of optical filters and optical modulators related to one or more of the following items: modulation speed, frequency selectivity, spectral range of operation, noise characteristics, device cost, Heat dissipation, device size, device scalability, and device power dissipation

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