John Edward Bowers

University of California, Santa Barbara | UCSB · Department of Electrical and Computer Engineering

Integrated photonic microresonators have become an essential resource for generating photonic qubits for quantum information processing, entanglement distribution and networking, and quantum communications. The pair generation rate is enhanced by reducing the microresonator radius, but this comes at the cost of increasing the frequency mode spacing...

The direct growth of III-V lasers on silicon has the potential to allow for low-cost production of silicon photonic integrated circuits on a 300 mm wafer-scale. However, coupling loss severely limits the performance in current implementations of direct growth processes due to the growth of undesirable polycrystalline material on silicon dioxide sid...

The direct growth of III-V lasers on silicon has the potential to allow for low-cost production of silicon photonic integrated circuits on a 300 mm wafer-scale. However, coupling loss severely limits the performance in current implementations of direct growth processes due to the growth of undesirable polycrystalline material on silicon dioxide sid...

Heterogeneous integration of GaAs-based lasers with frequency doubling waveguides presents a clear path to scalable coherent sources in the so-called green gap, yet frequency doubling systems have so far relied on separately manufactured lasers to deliver enough power for second harmonic generation. In this work, we propose a photonic integrated ci...

Next-generation communications, radar, and navigation systems will extend and exploit the higher bandwidth of the millimeter-wave domain for increased communication data rates as well as radar with higher sensitivity and increased spatial resolution. However, realizing these advantages will require the generation of millimeter-wave signals with low...

Processing information in the optical domain promises advantages in both speed and energy efficiency over existing digital hardware for a variety of emerging applications in artificial intelligence and machine learning. A typical approach to photonic processing is to multiply a rapidly changing optical input vector with a matrix of fixed optical we...

Rapid progress in photonics has led to an explosion of integrated devices that promise to deliver the same performance as table-top technology at the nanoscale, heralding the next generation of optical communications, sensing and metrology, and quantum technologies. However, the challenge of co-integrating the multiple components of high-performanc...

The invention of the laser unleashed the potential of optical metrology, leading to numerous advancements in modern science and technology. This reliance on lasers, however, also sets a bottleneck for precision optical metrology which is complicated by sophisticated photonic infrastructure required for delicate laser-wave control, leading to limite...

Compact photonic systems that offer high frequency stability and low noise are of increasing importance to applications in precision metrology, quantum computing, communication, and advanced sensing technologies. However, on-chip resonators comprised of dielectrics cannot match the frequency stability and noise characteristics of Fabry-Perot caviti...

The development of manufacturable and scalable integrated nonlinear photonic materials is driving key technologies in diverse areas, such as high-speed communications, signal processing, sensing, and quantum information. Here, we demonstrate a nonlinear platform—InGaP-on-insulator—optimized for visible-to-telecommunication wavelength χ(2) nonlinear...

We explore how III-V semiconductor microring resonators can efficiently generate photon pairs and squeezed vacuum states via spontaneous parametric down-conversion by utilizing their built-in quasi phase matching and modal dispersion. We present an analytic expression for the biphoton wave function of photon pairs generated by weak pump pulses, and...

Coherent optics has profoundly impacted diverse applications ranging from communications, LiDAR to quantum computations. However, developing coherent systems in integrated photonics comes at great expense in hardware integration and energy efficiency. Here we demonstrate a high-coherence parallelization strategy for advanced integrated coherent sys...

Most current Data Center Interconnects (DCI) use intensity modulation direct detection (IMDD) configurations due to their low complexity and cost. However, significant scaling challenges allow coherent solutions to become contenders in these short reach applications. We present an O-band coherent optical fiber transmission system based on Quantum D...

We report the development of high quality InAs quantum dots with an ultra-low density of 2 × 10⁷ cm⁻² on (001) GaAs substrates. A significant reduction in the emission wavelength inhomogeneity has been observed. A representative dot has been characterized under cryogenic temperatures, demonstrating a close-to-ideal antibunching of both the exciton...

Microcombs are advancing optical frequency comb technology towards a chip-integrable form. Here, we characterize a microwave signal source based upon the two-point optical frequency division (2P-OFD) technique. The system uses a frequency microcomb to transfer relative frequency stability of two low-noise optical oscillators to the microcomb repeti...

Swept laser interferometry is an extremely powerful solution embedded in several recent technologies such as absolute distance measurement, light detection and ranging (LiDAR), optical frequency domain reflectometry, optical coherence tomography, microresonator characterization, and gas spectroscopy. Nonlinearity in the optical frequency sweeping o...

High-performance, high-volume-manufacturing Si3N4 photonics requires extremely low waveguide losses augmented with heterogeneously integrated lasers for applications beyond traditional markets of high-capacity interconnects. State-of-the-art quality factors (Q) over 200 million at 1550 nm have been shown previously; however, maintaining high Qs thr...

This paper explores the impact of gain medium on linewidth narrowing in integrated self-injection locked III–V/SiN lasers, theoretically and experimentally. We focus on the effects of carrier densities of states in zero- and two-dimensional structures due to quantum-dot and quantum-well confinement. The theoretical approach includes (a) multimode l...

Swept laser interferometry is an extremely powerful solution embedded in several recent technologies such as absolute distance measurement, light detection and ranging, optical frequency domain reflectometry, optical coherence tomography, microresonator characterization, and gas spectroscopy. Nonlinearity in the optical frequency sweeping of tunabl...

In the last decade, remarkable advances in integrated photonic technologies have enabled table-top experiments and instrumentation to be scaled down to compact chips with significant reduction in size, weight, power consumption, and cost. Here, we demonstrate an integrated continuously tunable laser in a heterogeneous gallium arsenide-on-silicon ni...

Low-confinement silicon nitride (SiN) waveguides offer ultra-low losses but require wide bend radii to avoid radiative losses. To realize the benefits of silicon nitride in a heterogeneous laser while maintaining a small footprint, we employ metal-coated etched facets and transversely coupled Fabry–Perot resonators as mirrors. Heterogeneous quantum...

Kelly sidebands are a special type of dispersive wave that appear in mode-locked systems and they have recently been observed by pulsed excitation in integrated microcombs. Here, Kelly sidebands are generated by continuous-wave excitation in a partially coupled racetrack-resonator microcomb. The coupled-racetrack system supports two optical bands s...

Correlated photon-pair sources are key components for quantum computing, networking, and sensing applications. Integrated photonics has enabled chip-scale sources using nonlinear processes, producing high-rate entanglement with sub-100 microwatt power at telecom wavelengths. Many quantum systems operate in the visible or near-infrared ranges, neces...

The development of manufacturable and scalable integrated nonlinear photonic materials is driving key technologies in diverse areas such as high-speed communications, signal processing, sensing, and quantum information. Here, we demonstrate a novel nonlinear platform -- InGaP-on-insulator -- optimized for visible-to-telecommunication wavelength $\c...

High-performance, high-volume-manufacturing Si3N4 photonics requires extremely low waveguide losses augmented with heterogeneously integrated lasers for applications beyond traditional markets of high-capacity interconnects. State-of-the-art quality factors (Q) over 200 million at 1550 nm have been shown previously; however, maintaining high Qs thr...

Distributed feedback laser diodes (DFBs) serve as simple, compact, narrow-band light sources supporting a wide range of photonic applications. Typical linewidths are on the order of sub-MHz for free-running III-V DFBs at infrared wavelengths, but linewidths of short-wavelength GaN-based DFBs are considerably worse or unreported. Here, we present a...

Ultralow-noise laser sources are crucial for a variety of applications, including microwave synthesizers, optical gyroscopes and the manipulation of quantum systems. Silicon photonics has emerged as a promising solution for high-coherence applications due to its ability to reduce the system size, weight, power consumption and cost. Semiconductor la...

The architecture and component technology of a low power, high capacity, short reach optical interconnect are detailed. Measurements from high-performance 300 mm silicon photonics components that comprise the system are shown, along with a quantum-dot mode-locked laser 20-channel comb source with free space wall plug efficiencies up to 17%, advance...

Optical nonreciprocity plays a key role in almost every optical system, directing light flow and protecting optical components from backscattered light. Controllable forms of on-chip nonreciprocity are needed for the robust operation of increasingly sophisticated photonic integrated circuits (PICs) in the context of classical and quantum computatio...

High- Q microresonators are indispensable components of photonic integrated circuits and offer several useful operational modes. However, these modes cannot be reconfigured after fabrication because they are fixed by the resonator’s physical geometry. In this work, we propose a Moiré speedup dispersion tuning method that enables a microresonator de...

Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb1–3. Such systems, however, are...

Thin-film lithium niobate (TFLN) is an attractive platform for photonic applications on account of its wide bandgap, its large electro-optic coefficient, and its large nonlinearity. Since these characteristics are used in systems that require a coherent light source, size, weight, power, and cost can be reduced and reliability enhanced by combining...

Tunable optical frequency combs offer a flexible solution for specific applications such as dual-comb spectroscopy, optical communications and microwave photonics, delivering improved precision, compatibility, and performance. However, previously, there has been a trade-off between reconfigurability and system simplicity in comb generation. Here, w...

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...

After extended aging, InAs quantum dot lasers form dislocation loops in the active region due to the coalescence of point defects. The point-defect formation process drives gradual laser degradation and is a key impediment to long-life lasers.

We demonstrate a heterogeneously integrated self-injection locked lithium niobate laser via direct bonding. The single mode lasing power is as high as 16 mW with a side mode suppression ratio over 50 dB.

We report the first O-band coherent transmission using a comb laser and a silicon photonics modulator. We achieved greater than 8.5 Tbps using 19 lines over 10km at 56 Gbaud DP-32QAM.

A compact co-packaged micro Fabry-Perot reference cavity integrated with photonic circuits achieves a redirected signal, 14.2 dB back-reflection suppression, and 79.5% cavity mode matching efficiency.

For the first time, we analyze the optical degradation of 1.3 mm InAs quantum dot laser diodes (QD LDs) epitaxially grown on silicon as a function of the number of dot-in-a-well layers (DWELLs). To this aim, we tested the reliability of two kinds of devices differing only in the number of DWELLs in the active region: QD LDs with three vs. five quan...

We present 100-mm wafer scale fabrication of the high χ ⁽²⁾ and χ ⁽³⁾ InGaP-on-insulator platform. Microring resonators with Q > 340,000 and propagation losses down to 1.72 dB/cm show promise for integrated quantum photonic applications.

We present III-V-on-Si 3 N 4 chip-scale lasers operating from 765-795 nm with < 5 kHz intrinsic linewidth and > 100 GHz mode-hop-free tuning. We demonstrate their application for nonlinear photonics with Si 3 N 4 microring resonators, atomic spectroscopy, and locking to ⁸⁷ Rb.

Counter-propagating solitons are generated in CMOS-ready coupled microresonators featuring normal dispersion. In each direction, the soliton mode locks and compensates the dispersion through the formation of a pulse pair. Both the spectra and the radiofrequency beatnotes of counter-propagating solitons are observed.

We demonstrate fully passive optical isolators in silicon nitride nanophotonics using the intrinsic Kerr nonlinearity. These devices serve to both stabilize and isolate on-chip lasers, reducing the linewidth of DFB lasers by orders of magnitude.

We report a >100 GHz mode-hop-free tunable III-V-on-Si 3 N 4 laser operating from 770-785 nm with < 5 kHz intrinsic linewidth. We demonstrate pumping of a high- Q Si 3 N 4 microresonator entangled-photon pair source and locking to the ⁸⁷ Rb D2 line.

A hybrid-integrated visible laser source is demonstrated using the photogalvanic effect. Self-injection locking of a 1560 nm semiconductor laser to a high-Q Si 3 N 4 resonator generates high-coherence 780 nm emission (4 Hz ² /Hz frequency noise floor).

Multi-color co-propagating and counter-propagating solitons are generated using a coupled-ring microresonator in the ultra-low-loss Si 3 N 4 platform. Soliton spectra and beatnotes are measured and potential applications are discussed.

This paper reports on an investigation of the frequency-modulated comb operation in a quantum-dot laser. Both the amplitude-modulated and the frequency-modulated combs can be generated independently from the same device through bias and the engineering of the optical nonlinearities.

We calculate the rate of spontaneous parametric down-conversion, and generated biphoton wavefunction, in an AlGaAs microring resonator designed to take full advantage of the quasi-phase matching occurring as the light propagates around the ring.

We generate millimeter-waves up to 118 GHz via heterodyning two photonic chip lasers which are phase-locked to the same miniature F-P cavity. Phase noise as low as − 120 dBc/Hz at 40 kHz offset is achieved.

Microwave signal generation with record-low phase noise is demonstrated using a microcomb. The results use 2-point optical-frequency-division with a frequency-agile dispersive wave as a spectral endpoint. The compact all-solid-state reference cavity features a record Q- factor.

We present 100-mm wafer fabrication of InGaP-on-insulator—a promising integrated quantum photonic platform with strong χ ⁽ ² ⁾ and χ ⁽ ³ ⁾ . We achieve 3.25 dB/cm waveguide loss and microresonators with Q > 160,000 for entangled-pair generation.

We experimentally demonstrate PAM-4 optical transmission beyond 224 Gbps based on an ultrahigh-bandwidth slow-light silicon modulator in C-band with the combination of the artificial neural network equalizers.

We demonstrate a sub-kHz linewidth integrated Pockels laser with a mode-hop-free linear frequency modulation range of 15 GHz, and an on-chip power of 5.4 mW.

Using integrated photonic chip components for ’2-point’ optical frequency division, we generate a 20 GHz microwave signal with phase noise of –135 dBc/Hz at 10 kHz offset.

We observed Floquet Chern insulator of light based on periodically driven nonlinear photonic crystal slabs. Energy gaps with non-trivial topology are extracted where photonic Floquet bands cross, indicating strong Floquet couplings.

We report an AlGaAs microresonator array enabling dense multiplexing of high-rate 1550 nm entangled-pair sources. Quantum combs are offset by 12.5 GHz and pumped with an electro-optic comb producing up to 4 GHz/mW ² pair rate per resonator.

We report nonlinear integrated photonic microresonator designs enabling > 1 THz/mW ² broadband pair generation rates. Simulations show a novel cross-polarized type-1 four-wave mixing phase-matching technique to further extend the bandwidth deeper into the visible spectrum.

Non-reciprocal platforms can offer several key advantages for scalable and efficient photonic computing. In this talk, I will present our recent experimental work validating the use of non-reciprocal materials to implement high-endurance memory for photonic computing. Full-text article not available; see video presentation