Design of Monolithic 2D Optical Phased Arrays Heterogeneously Integrated with On-Chip Laser Arrays Based on SOI Photonic Platform

Abstract

In this work, heterogeneous integration of both two-dimensional (2D) optical phased arrays (OPAs) and on-chip laser arrays based on a silicon photonic platform is proposed. The tunable multi-quantum-well (MQW) laser arrays, active switching/shifting arrays, and grating antenna arrays are used in the OPA module to realize 2D spatial beam scanning. The 2D OPA chip is composed of four main parts: (1) tunable MQW laser array emitting light signals in the range of 1480–1600 nm wavelengths; (2) electro-optic (EO) switch array for selecting the desired signal light from the on-chip laser array; (3) EO phase-shifter array for holding a fixed phase difference for the uniform amplitude of specific optical signal; and (4) Bragg waveguide grating antenna array for controlling beamforming. By optimizing the overall performances of the 2D OPA chip, a large steering range of 88.4° × 18° is realized by tuning both the phase and the wavelength for each antenna. In contrast to the traditional thermo-optic LIDAR chip with an external light source, the overall footprint of the 2D OPA chip can be limited to 8 mm × 3 mm, and the modulation rate can be 2.5 ps. The ultra-compact 2D OPA assembling with on-chip tunable laser arrays using hybrid integration could result in the application of a high-density, high-speed, and high-precision lidar system in the future.

Photonic Integrated Circuits for an Optical Phased Array

“…While applying an on-chip light source can improve the performance of OPAs [82][83][84][85][86][87][88][89], its advantages over other types of PICs, such as optical transceivers or sensors, are not significant. The challenges in installing an on-chip light source on an OPA are the same as those involved in developing a light source on a silicon platform, which is primarily due to the indirect bandgap of silicon.…”

“…The challenges in installing an on-chip light source on an OPA are the same as those involved in developing a light source on a silicon platform, which is primarily due to the indirect bandgap of silicon. Nonetheless, researchers have reported the successful use of heterogeneous integrated InP light sources [83][84][85][86]88] and Erbium-doped light sources [87] for PIC-OPAs. Integrating an on-chip light source can significantly reduce the size and complexity of the OPA system, eliminating the need for an external laser.…”

Editorial for the Special Issue on Optics and Photonics in Micromachines

“…In this Special Issue, we are glad to collect 15 research articles covering a broad area, including optical field modulation [ 11 ], laser fabrication techniques [ 12 , 13 ], optical measurement [ 14 , 15 , 16 , 17 , 18 ], on-chip photonic devices [ 19 , 20 , 21 , 22 ], super-resolution imaging [ 23 , 24 ], and related theoretical [ 25 ] investigations.…”

“…Chen et al [ 20 ] developed a plenoptic camera based on an electrically tunable liquid crystal with a hexagonal-period liquid crystal array for all-in-focus polarimetric imaging, dedicated to providing more optical information for both scientific and daily applications. Yue et al [ 22 ] proposed a method to integrate 2D optical phased arrays with an on-chip multi-quantum-well laser array heterogeneously based on a silicon photonic platform. By employing four key components, including a multi-quantum-well laser array, electro-optic switch array, phase-shifter array and a Bragg-waveguide-grating antenna array, the device can realize 2D spatial beam scanning with a large steering range of 88.4° × 18°.…”