Wim Bogaerts

• Professor at Ghent University

We present a photonic engine that processes both optical and microwave signals, and can convert signals between the two domains. Our photonic chip, fabricated in IMEC’s iSiPP50G silicon photonics process, is capable of both generation and detection of analog electrical and optical signals, and can program user-defined filter responses in both domai...

A new electro‐optic phase shifter device architecture consisting of two lateral rail electrodes in doped silicon close to a waveguide with a liquid crystal cladding is demonstrated. Starting with a completed silicon photonics wafer of IMEC's iSiPP50G platform (including modulators, detectors, and metallization), the back‐end‐of‐line stack is opened...

Mach-Zehnder interferometers (MZIs) are essential components that are used in a variety of wavelength division multiplexing (WDM) systems. Wavelength-sensitive straight directional couplers (DCs) are usually used as the beam splitter and combiner in traditional waveguide-based MZIs, which often limit the operational bandwidth and cause additional i...

2x2 couplers are crucial in many photonics applications but are often wavelength-sensitive. Alternative designs could be large, complex, or lossy. We present a broadband ultra-compact adiabatic coupler with minimal coupling variation and the least silicon taper length of 1.44 um, to our best knowledge.

We experimentally demonstrate a new methodology for the extraction of dimensions from silicon-on-insulator (SOI) strip waveguides manufactured in IMEC’s iSiPP50G silicon photonics platform. The effective index (n eff ) and group index (n g ) of the waveguide are determined from the spectral data of a single high-order Mach-Zehnder Interferometer (M...

Dispersive optical phased arrays (DOPAs) offer a method for fast 2D beam scanning for solid-state LiDAR with a pure passive operation, and therefore low control complexity and low power consumption. However, in terms of scalability, state-of-the-art DOPAs do not easily achieve a balanced performance over the specifications of long-range LiDAR, incl...

Electro-optical modulators are essential components in optical communication systems. They encode an electrical waveform onto an optical carrier. However, their performance is often limited by inherent electro-optic processes and imperfections in existing integrated designs, which limit their adaptability to diverse applications. This paper present...

This work presents a computationally efficient transmission matrix model and optimization scheme for the design of silicon nitride grating couplers in integrated scattering-based flow cytometry systems. The proposed model accurately simulates the optical power flow through the grating coupler and microfluidic channel system, enabling precise evalua...

This roadmap consolidates recent advances while exploring emerging applications, reflecting the remarkable diversity of hardware platforms, neuromorphic concepts, and implementation philosophies reported in the field. It emphasizes the critical role of cross-disciplinary collaboration in this rapidly evolving field.

In the rapidly evolving domain of Photonic Integrated Circuits, reconfigurability is making strides through tunable waveguide elements, facilitating ‘general-purpose’ programmable waveguide grids. Routing in modern programmable photonic networks is challenging due to the numerous possibilities that exist for assigning photonic circuits in the grid....

We propose an automatic approach for implementing light processing functions on programmable photonic integrated circuits. Our approach offers two unprecedented and significant advantages. Firstly, it is generalizable to any topology, including triangular, square, and hexagonal meshes, and any linear light processing function with a frequency domai...

The wavelength-insensitive response of the bent directional coupler (DC) is rigorously studied by means of coupled mode theory analysis. On that basis, we demonstrate an experimental-based coupling model for the bent DC capable of achieving wavelength-insensitive coupling for arbitrary coupling ratios. The measured devices exemplify wavelength-inse...

Programmable photonic integrated circuits (PPICs) are an emerging technology recently proposed as an alternative to custom-designed application-specific integrated photonics. Light routing is one of the most important functions that need to be realized on a PPIC. Previous literature has investigated the light routing problem from an algorithmic or...

Programmable photonic integrated circuits (PPICs) emerge as a novel technology with an enormous potential for ground-breaking innovation. Different architectures are currently being considered that dictate how waveguides should be connected to realize a broadly usable circuit. We focus on the effect of varying connectivity architectures on the rout...

We present a photonic engine that processes both optical and microwave signals, and can convert signals between the two domains. Our photonic chip, fabricated in IMEC's iSiPP50G silicon photonics process, is capable of both generation and detection of analog electrical and optical signals, and can program user-defined filter responses in both domai...

We present how a conventional Si waveguide grating coupler can be integrated with a polymerizable liquid crystal polarization grating to provide vertical coupling between optical fibers and planar waveguides. The implementation involves the deposition of a liquid crystal polymer film onto the surface of the planarized photonic chip. To achieve opti...

Silicon photonics has developed into a mainstream technology driven by advances in optical communications. The current generation has led to a proliferation of integrated photonic devices from thousands to millions-mainly in the form of communication transceivers for data centers. Products in many exciting applications, such as sensing and computin...

We present the current state of the art in micro-transfer printing for heterogeneously integrated silicon photonic integrated circuits. The versatility of the technology is highlighted, as is the way ahead to make this technology a key enabler for next-generation photonic systems-on-chip.

We present an approach for the heterogeneous integration of InP semiconductor optical amplifiers (SOAs) and lasers on an advanced silicon photonics (SiPh) platform by using micro-transfer-printing (µTP). After the introduction of the µTP concept, the focus of this paper shifts to the demonstration of two C-band III-V/Si photonic integrated circuits...

Correction for ‘Integrated 4-terminal single-contact nanoelectromechanical relays implemented in a silicon-on-insulator foundry process’ by Yingying Li et al. , Nanoscale , 2023, https://doi.org/10.1039/d3nr03429a.

We present a single photonic chip that processes both optical and microwave signals, and can convert signals between the two domains. Our chip, fabricated in IMEC’s iSiPP50G silicon photonics process, is capable of both generation and detection of analog electrical and optical signals, and can program a user-defined filter response in both domains....

We present an approach for the heterogeneous integration of InP semiconductor optical amplifiers (SOAs) and lasers on an advanced silicon photonics (SiPh) platform by using micro-transfer-printing (μTP). After the introduction of the μTP concept, the focus of this paper shifts to the demonstration of two C-band III-V/Si photonic integrated circuits...

We present an approach for the heterogeneous integration of InP semiconductor optical amplifiers (SOAs) and lasers on an advanced silicon photonics (SiPh) platform by using micro-transfer-printing (μTP). After the introduction of the μTP concept, the focus of this paper shifts to the demonstration of two C-band III-V/Si photonic integrated circuits...

Integrated nanoelectromechanical (NEM) relays can be used instead of transistors to implement ultra-low power logic circuits, due to their abrupt turn off characteristics and zero off-state leakage. Further, realizing circuits with 4-terminal (4-T) NEM relays enables significant reduction in circuit device count compared to conventional transistor...

A novel wideband parametric baseband macromodeling technique for passive photonic devices and circuits is presented. It allows to efficiently estimate the baseband scattering representations of a linear, passive photonic system as a function of a set of design variables, such as geometrical layout or substrate features. The proposed technique relie...

Photonic Integrated Circuits are rapidly becoming more reconfigurable using tunable waveguide elements, coming closer to realizing ‘general purpose’ programmable waveguide meshes. To utilize the full potential of such circuits, special software routines need to be developed to determine the optical paths inside the mesh. Right now, current methods...

Long-distance light detection and ranging (LiDAR) applications require an aperture size in the order of 30 mm to project 200–300 m. To generate such collimated Gaussian beams from the surface of a chip, this work presents a novel waveguide antenna concept, which we call an “optical leaky fin antenna,” consisting of a tapered waveguide with a narrow...

Programmable photonic integrated circuits (PPICs) are an emerging technology recently proposed as an alternative to custom-designed application-specific integrated photonics. Light routing is one of the most important functions that need to be realized on a PPIC. Previous literature has investigated the light routing problem from an algorithmic or...

Silicon photonics has developed into a mainstream technology driven by advances in optical communications. The current generation has led to a proliferation of integrated photonic devices from thousands to millions - mainly in the form of communication transceivers for data centers. Products in many exciting applications, such as sensing and comput...

Silicon photonics has emerged as a mature technology that is expected to play a key role in critical emerging applications, including very high data rate optical communications, distance sensing for autonomous vehicles, photonic-accelerated computing, and quantum information processing. The success of silicon photonics has been enabled by the uniqu...

Linear light-processing functions (e.g., routing, splitting, filtering) are key functions requiring configuration to implement on a programmable photonic integrated circuit (PPIC). In recirculating waveguide meshes (which include loop-backs), this is usually done manually. Some previous results describe explorations to perform this task automatical...

Ring resonators are a vital element for filters, optical delay lines, or sensors in silicon photonics. However, reconfigurable ring resonators with low-power consumption are not available in foundries today. We demonstrate an add-drop ring resonator with the independent tuning of round-trip phase and coupling using low-power microelectromechanical...

Passive photonic integrated circuits (PICs) can be easily characterized in the frequency-domain, but their accurate time-domain performance evaluation is a hurdle for system-level designers, especially when dealing with resonant circuits having highly dispersive behavior, such as ring resonators. In this paper, a new equivalent circuit modeling and...

ABSTRACT: Silicon photonic devices are very sensitive to process variation, and it is important for circuit designers that they can predict the effect of this variability during the design phase, and optimize their design for both performance and yield. This requires an accurate predictive model of the spatial variations induced by the fabrication...

Linear light processing functions (e.g., routing, splitting, filtering) are key functions requiring configuration to implement on a programmable photonic integrated circuit (PPIC). In recirculating waveguide meshes (which include loop-backs), this is usually done manually. Some previous results describe explorations to perform this task automatical...

Low-power and compact phase shifters are crucial for large photonic circuits, both to cope with variability and to create programmable waveguide circuits scaling to thousands of tuning elements. This work demonstrates a liquid crystal phase shifter where there is a lateral silicon electrode "rail" on one side of the waveguide core. Using this archi...

We propose a novel filter circuit that incorporates a double ring resonator with a balanced Mach–Zehnder interferometer (MZI). The circuit has a response equivalent to a conventional ring loaded MZI filter, but with added flexibility in terms of configurability. The second-order filter can also be cascaded to realize higher-order filters. The circu...

We demonstrate low-power and non-volatile MEMS actuators on an industrially established silicon photonics platform. The compact electrostatically actuated phase shifters and tunable couplers enable large-scale programmable photonic integrated circuits.

Applications of silicon photonics range from sensing to microwave processing. However, low-power active filters with long FSRs are lacking. We demonstrate an add-drop ring filter with 4 nm FSR and nW-level MEMS tuning of phase and coupling.

We demonstrate a C-band optical transmitter with an integrated widely-tunable III-V-on-silicon laser on the imec iSiPP50G platform using micro-transfer printing. Back-to-back operation at 40 Gbit/s non-return-to-zero On-Off keying over the C-band is presented.

Programmable photonic chips allow flexible reconfiguration of on-chip optical connections, controlled through electronics and software. We will present the recent progress of such complex photonic circuits powered by silicon photonic MEMS actuators.

In this work, we summarize our recent advances in 2D beamsteering using optical phased arrays operating in NIR and SWIR wavelengths, covering different architectures and steering techniques based on active phase shifting and wavelength tuning.

The emerging fields of silicon (Si) photonic micro-electromechanical systems (MEMS) and optomechanics enable a wide range of novel high-performance photonic devices with ultra-low power consumption, such as integrated optical MEMS phase shifters, tunable couplers, switches, and optomechanical resonators. In contrast to conventional SiO2-clad Si pho...

Programmable photonic integrated circuits are emerging as an attractive platform for applications such as quantum information processing and artificial neural networks. However, current programmable circuits are limited in scalability by the lack of low-power and low-loss phase shifters in commercial foundries. Here, we demonstrate a compact phase...

We propose a novel filter circuit that incorporates a double ring resonator with a balanced Mach-Zehnder interferometer (MZI).The circuit has a response equivalent to a conventional ring loaded MZI filter, but with added flexibility in terms of configurability. The second-order filter can also be cascaded to realize higher-order filters. The circui...

Complex vector fitting (CVF) is a robust method to efficiently and accurately model general linear and passive baseband systems. Such models are important for the analysis and design of modern electronic and optical communication systems. This letter introduces an efficient toolbox implementation of the CVF algorithm. The effectiveness of the code...

Optical modulation plays arguably the utmost important role in microwave photonic (MWP) systems. Precise synthesis of modulated optical spectra dictates virtually all aspects of MWP system quality including loss, noise figure, linearity, and types of functionalities that can be executed. However, for such a critical function, the versatility to gen...

Photonic Integrated Circuits (PICs) benefit from the technology advances in the semiconductor industry to incorporate an ever-increasing number of photonic components on a single chip to create large-scale photonic integrated circuits. We here present a broadband, compact and low-loss Silicon Photonic MEMS switch based on a Single-Pole Double-Throw...

MEMS enable low power tuners in silicon photonics, but existing phase shifters lack in range, speed, and loss. We implement a 2 π phase shifter with a 1.54 μs time constant and 0.5 dB insertion loss in IMEC’s iSiPP50G platform.

Photonic integrated circuits are becoming increasingly more complex, especially with the emergence of programmable photonic circuits. These require many tunable photonic elements, such as electro-optic phase shifters and tunable couplers. We will discuss our progress in compact, low-power silicon photonics actuators based on heaters, liquid crystal...

We present a silicon photonics technology extended with low-power MEMS scalable to large circuits. This enables us to make photonic waveguide meshes that can be reconfigured using electronics and software.

Stimulated Brillouin Scattering (SBS) is demonstrated on a standard active silicon photonics platform, the forward SBS gain and opto-mechanical coupling rates are calculated for two different rib waveguide geometries.

Optical modulation plays arguably the utmost important role in microwave photonic (MWP) systems. Precise synthesis of modulated optical spectra dictates virtually all aspects of MWP system quality including loss, noise figure, linearity, and the types of functionality that can be executed. But for such a critical function, the versatility to genera...