Compact InGaAsP/InP 3 × 3  multimode-interference coupler-based electro-optic switch

Abstract

Optical switches are key components in data links for optical communication networks requiring low crosstalk and insertion loss, high switching speed, and power efficiency. A multimode-interference (MMI)-coupler-based switch with multiple inputs and outputs serving as a switching unit is desired toward forming a large-scale switch matrix. Here we demonstrate a compact 3×3 MMI coupler electro-optic switch based on the carrier injection effect on InGaAsP/InP substrates. This switch device is 2780 μm long by 18 μm wide. The switching states can be controlled by two index-modulation regions through applied bias voltages. Our simulation results show that the device exhibits low crosstalk of <-22 dB, high extinction ratio of ≳23 dB, low electrical switching energy of ∼2.0 pJ/bit, maximum operational frequency of ∼1.0 GHz, and optical bandwidth of ∼20 nm in the C band. We experimentally validated one of the switching states on a fabricated device with maximum current injections of ∼25 mA under combined bias voltages of ∼2.5 and ∼3.0 V. Such monolithic integration schemes make them an ideal candidate for future on-chip photonic integrated circuits.

Racetrack Ring Resonator Integrated with Multimode Interferometer Structure Based on Low-Cost Silica–Titania Platform for Refractive Index Sensing Application

“…They are generally used in various Planar Lightwave Circuit (PLC) applications, including power splitters, optical switches, and wavelength division multiplexers/demultiplexers. MMI couplers based on different materials, such as LiNBO 3 [4], SOI [5], InP [6], polymer [7], silica-on-silicon (SOS) [8], etc., have been reported. The versatility and efficiency of MMI couplers make them a crucial component in modern integrated photonics devices.…”

Unitary transformation of general nonoverlapping-image multimode interference couplers with any input and output ports*

“…The optical behaviors of light in MMI couplers have been described theoretically so far. [1][2][3][4][5][6] Many complex optical devices based on MMI couplers have been investigated such as optical couplers, [7][8][9] switches, [10][11][12][13][14] routers, [15,16] and hybrids. [17][18][19][20][21] The method of designing these devices was applied to a specific MMI coupler and the output amplitude and phase information corresponding to different input light were calculated.…”

Compact Low-Loss Optical 72$^{\circ }$ Hybrid Based on Nonoverlapping-Image Multimode Interference Coupler in Silicon-on-Insulator

“…Some theoretical aspects have been developed [1]- [6] to describe the optical behavior of light in MMI couplers so far. Many complex optical devices based on MMI couplers have been investigated such as switches [7], [8], sensors [9], [10], routers [11], [12] and optical hybrids [13]- [18].…”