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A single pump generates counter-propagating Brillouin laser, enabling dual-soliton excitation in an over-modal microresonator. Via tuning the pump detuning, the dual-soliton demonstrates tunable repetition offset ranging from 8.4 MHz to 367 MHz.

We present our implementation of a 4F system integrated into a single Silicon Photonic chip to perform the high-speed Convolutional Neural Network by using optical on-chip FFT. We show the Silicon Photonic design, the initial optical response, and the packaging of the 4F chip.

We characterized timing jitter of dispersion-managed frequency microcomb with femtosecond timing resolution through fiber interferometry for the first time. The measured timing jitter PSD and integrated timing jitter are 0.4 as2/Hz and 1.7 fs.

We examine and identify mid-infrared transitions of 77Se+ deep-donors in silicon via absorption spectroscopy. The optically-accessible Se nuclear spins, with potentially long coherence, can serve as on-chip spin-photon interfaces for quantum communications and repeater architectures.

We observed evidence of spectral-phase-coherence in a singly-resonant biphoton frequency comb’s second-order cross-correlation function, and we verified the state’s time-energy entanglement by measuring Franson interference in 2 time-bins that violate the Bell inequality.

We utilized an integrated optical frequency comb with an analog front-end to measure distance via a hybrid pulsed-coherent approach. We experimentally measure distance to a reflector 2m away, with 7μm precision and 250μm accuracy.

We present a programmable on-chip photonic machine learning system based on the joint transform correlator. Testing the system on MNIST dataset shows 96.9% accuracy with even 10% signal delay.

We demonstrate high-resolution cryogenic photoluminescence measurements on exciton complexes emitting ≈ 1 µm of a single-site-controlled highly-symmetric quantum dot-nanocavity system. Observed fine spectral features uncover the C3 v QD symmetry and cavity quantum electrodynamics.

We experimentally observed spatiotemporal dynamics of soliton crystals in a Kerr microresonator. We numerically reproduce our observations and further confirm them using an ultrafast temporal imaging system.

Flat optical spectra are desired in many frequency microcomb applications such as ultrabroadband optical communication, interconnects, spectroscopy, and metrology. Here we achieve flat-top spectral envelopes via deterministic control in soliton crystal microcombs.

We present our implementation of a Convolution Neural Network employing an Integrated Photonic Chip (PIC) to perform the high-speed optical FFT, showing the Silicon Photonic design, the initial optical response, and packaging.

We demonstrate a single-photon SWAP gate between polarization and spatial-momentum qubits on a silicon-on-oxide chip. Phase coherence of the SWAP gate operation is confirmed via single-photon self-interference, with visibility up to 98.89%.

We present a comparison of TE soliton microcomb generation with thermal compensation from the TE auxiliary pump and TM auxiliary pump. The amplitude noise in the soliton state can be eliminated with an orthogonal dual-pump configuration. The soliton repetition frequency phase noise of -72 dBc/Hz and a 450 Hz of linewidth are obtained.

We report state-of-the-art metasurface optical elements enabling our high-resolution full-color prototype, via the combination of analytical modeling, numerical simulations, and experiments. Our prototype device has achieved field-of-view >40o, high output efficiency (>1%), and 2K resolution.

Femtosecond mode-locked laser frequency combs have served as the cornerstone in precision spectroscopy, all-optical atomic clocks, and measurements of ultrafast dynamics. Recently frequency microcombs based on nonlinear microresonators have been examined, exhibiting remarkable precision approaching that of laser frequency combs, on a solid-state chip-scale platform and from a fundamentally different physical origin. Despite recent successes, to date, the real-time dynamical origins and high-power stabilities of such frequency microcombs have not been fully addressed. Here, we unravel the transitional dynamics of frequency microcombs from chaotic background routes to femtosecond mode-locking in real time, enabled by our ultrafast temporal magnifier metrology and improved stability of dispersion-managed dissipative solitons. Through our dispersion-managed oscillator, we further report a stability zone that is more than an order-of-magnitude larger than its prior static homogeneous counterparts, providing a novel platform for understanding ultrafast dissipative dynamics and offering a new path towards high-power frequency microcombs.

This study investigates chaotic and spiking dynamics of mid-infrared quantum cascade lasers operating under external optical feedback and emitting at 5.5 $\mu {\text{m}}$ and 9 $\mu {\text{m}}$ . In order to deepen the understanding, the route to chaos is experimentally studied in the case of continuous-wave and current modulation operation. The non-linear dynamics are analyzed with bifurcation diagrams. While for quasi-continuous wave operation, chaos is found to be more complex, pure continuous wave pumping always leads to the generation of a regular spiking induced low-frequency fluctuations dynamics. In the latter, results show that by combining external optical feedback with periodic forcing and further induced current modulation allows a better control of the chaotic dropouts. This work provides a novel insight into the development of future secure free-space communications based on quantum cascade lasers or unpredictable optical countermeasure systems operating within the two transparency atmospheric windows hence between 3 $\mu {\text{m}}$ –5 $\mu {\text{m}}$ and 8.5 $\mu {\text{m}}$ –11 $\mu {\text{m}}$ .

Mid-infrared free-space optical communication has a large potential for high speed communication due to its immunity to electromagnetic interference. However, data security against eavesdroppers is among the obstacles for private free-space communication. Here, we show that two uni-directionally coupled quantum cascade lasers operating in the chaotic regime and the synchronization between them allow for the extraction of the information that has been camouflaged in the chaotic emission. This building block represents a key tool to implement a high degree of privacy directly on the physical layer. We realize a proof-of-concept communication at a wavelength of 5.7 μm with a message encryption at a bit rate of 0.5 Mbit/s. Our demonstration of private free-space communication between a transmitter and receiver opens strategies for physical encryption and decryption of a digital message., Free-space communication in the mid-IR domain has many potential applications, but security is still challenging. Here, the authors use chaos synchronization in a QCL-based free-space link as a way to increase privacy of such transmissions.

International audience; We experimentally display temporal chaotic waveforms in the mid-infrared domain with two different types of semiconductor lasers. The generated high-dimensional non-linear dynamics are of prime interest for private communications and physical random number generation.

We present a hybrid device based on graphene-coupled silicon (Si) photonic crystal (PhC) cavities, featuring triple light detection, modulation, and switching. Through depositing single-layer graphene onto the PhC cavity, the light-graphene interaction can be enhanced greatly, which enables significant detection and modulation of the resonant wavelength. The device is designed to generate a photocurrent directly by the photovoltaic effect and has an external responsivity of ∼14 mA/W at 1530.8 nm (on resonance), which is about 10 times higher than that off-resonance. Based on the thermo-optical effect of silicon and graphene, the device is also demonstrated in electro-optical and all-optical modulation. Also, due to the high-quality (Q) factor of the resonate cavity, the device can implement low threshold optical bistable switching, and it promises a fast response speed, with a rise (fall) time of ∼0.4 μs (∼0.5 μs) in the all-optical switch and a rise (fall) time of ∼0.5 μs (∼0.5 μs) in the electro-optical hybrid switch. The multifunctional photodetector, modulator, and optical bistable switch are achieved in a single device, which greatly reduces the photonic overhead and provides potential applications for future integrated optoelectronics.

Lidars are becoming common components for remote sensing in many emerging applications such as autonomous vehicle and facial recognition. To accurately visualize the point cloud for further data processing, metrics such as precision, sampling rate, and linearity are important. The concept of a sub-sampling pulsed-coherent lidar system [1] has demonstrated high precision and fast acquisition. The segmented time-of-flight (ToF) algorithm measures the phase shift of the carrier as fine ToF and counts the arrival time of the low-frequency mask’s envelope as intermediate and coarse ToF. Fig. 1(a) shows the down-conversion architecture in [1] using a simple LO generation which only uses dividers and a mixer to minimize the clock jitter. The performance based on the coherent detection, however, is limited by several factors. (1) The crosstalk between the reference clock and the echoed signal at the same frequency lowers the sensitivity and the linearity. Specifically, the reference leaks to the incoming signal path hence introducing an in-band spur. At the same time, the received signals with different power pull the clock phase and cause input-dependent phase shifts. (2) I/Q IF channels and two high-speed ADCs are required to reconstruct the mask’s envelope leading to high power consumption. Additionally, I/Q mismatch calibration process must be done prior to the normal acquisition. In this work, a local PLL synthesizes the LO to suppress the in-band reference leakage and crosstalk. A two-step down-conversion with digital down-mixing is implemented which improves the power efficiency and immunity to PVT variation without additional calibration. We also propose an inverter-based phase-invariant programmable gain amplifier (PI-PGA) that improves the linearity with a 40-dB tuning range. This calibration-free system achieves 6-μm precision and 30-μm INL Max with a 5-MSa/s sampling rate.

Dissipative Kerr solitons in resonant frequency combs offer a promising route for ultrafast mode-locking, precision spectroscopy and time-frequency standards. The dynamics for the dissipative soliton generation, however, are intrinsically intertwined with thermal nonlinearities, limiting the soliton generation parameter map and statistical success probabilities of the solitary state. Here, via use of an auxiliary laser heating approach to suppress thermal dragging dynamics in dissipative soliton comb formation, we demonstrate stable Kerr soliton singlet formation and soliton bursts. First, we access a new soliton existence range with an inverse-sloped Kerr soliton evolution—diminishing soliton energy with increasing pump detuning. Second, we achieve deterministic transitions from Turing-like comb patterns directly into the dissipative Kerr soliton singlet pulse bypassing the chaotic states. This is achieved by avoiding subcomb overlaps at lower pump power, with near-identical singlet soliton comb generation over twenty instances. Third, with the red-detuned pump entrance route enabled, we uncover unique spontaneous soliton bursts in the direct formation of low-noise optical frequency combs from continuum background noise. The burst dynamics are due to the rapid entry and mutual attraction of the pump laser into the cavity mode, aided by the auxiliary laser and matching well with our numerical simulations. Enabled by the auxiliary-assisted frequency comb dynamics, we demonstrate an application of automatic soliton comb recovery and long-term stabilization against strong external perturbations. Our findings hold potential to expand the parameter space for ultrafast nonlinear dynamics and precision optical frequency comb stabilization., Nonlinear optics: Keeping solitons warm and stable Ultrafast optical states called solitons can be prevented from thermally breaking down by carefully heating them with a laser, researchers in the US and China show. Solitons are optical fields that exist in isolation, like smoke rings in air or bubbles in water, and they could greatly improve precision laser measurements and spectroscopy. However, it is difficult to maintain robust soliton states due to nonlinear thermal effects that cause them to break down. Heng Zhou at UESTC, Chee Wei Wong at UCLA, and co-workers generated solitons by directing a ‘frequency comb’ source (comprising discrete, equally-spaced laser lines) onto a silicon nitride optical microcavity. Crucially, they employed a second laser to provide heating to the system and suppress the thermal nonlinearities. This enabled smooth transitions between useful soliton states, while avoiding chaotic intermediate states.

Femtosecond mode-locked laser frequency combs have served as the cornerstone in precision spectroscopy, all-optical atomic clocks, and measurements of ultrafast dynamics. Recently frequency microcombs based on nonlinear microresonators have been examined – affording remarkable precision approaching that of laser frequency combs, and now on a solid-state chip-scale platform and from a fundamentally different physical origin. Here we unravel the transitional dynamics of frequency microcombs from chaotic background routes to femtosecond mode-locking in real-time, enabled by our ultrafast temporal magnifier metrology and enlarged stability of dispersion-managed dissipative solitons. Through our dispersion-managed oscillator, we report a stability zone more than an order-of-magnitude larger than prior static homogeneous counterparts, providing a novel platform for understanding ultrafast dissipative dynamics and offering a new path towards high-power frequency microcombs.

The spontaneous breaking of symmetry and homogeneity through dissipative pattern formation is a long-standing fundamental examination in mathematics and nonlinear physics. Self-organized patterns arise in nature, and are postulated to occur from stochastically driven nonlinear processes. These threshold-dependent patterns can be remarkably robust in the presence of noise. In this talk we describe the dispersive dynamics in nonlinear resonator frequency microcombs and their statistical distributions. We describe the frame-by-frame fluctuations in the different microcomb states including fast breathers and their thresholds. These observed self-organized patterns support applications in communications and the understanding of nonlinear physics at the fundamental limits.

Augmented reality devices, as smart glasses, enable users to see both the real world and virtual images simultaneously. Recently, waveguides incorporating holographic optical elements have been utilized in various grating structures to reduce the size and weight of the smart glasses, instead of bulky free-space headsets. However, these devices typically still possess physical and performance limitations, which lead to limited display quality and high cost. Here we report metasurface optical elements as a platform solution to these shortcomings. Through careful control of dispersion in the excited propagation and diffraction modes, we design a high-resolution waveguide display to the human eye box, with large field-of-view and in a full-color implementation. Supported by our combination of analytical and numerical simulations, we examine a metasurface optical waveguide with high input-output efficiency and high-resolution, implemented in a single metasurface layer.

Ultrafast laser frequency microcombs provide equidistant coherent frequency markers over a broad spectrum, enabling new frontiers in chip-scale frequency metrology, laser spectroscopy, dense communications, precision metrology. Measuring and understanding the fundamental noise parameters in these high-clock-rate frequency microcombs are essential to advance the underlying physics and the precision microwave-optical clockwork. In this talk we describe the noise characteristics and timing jitter in adiabatic laser frequency microcombs. We compare and contrast the fundamental noise and fluctuation parameters for a series of laser frequency microcomb states, from multiple soliton to soliton crystals and single-soliton regimes. Each of the noise families and their noise coupling mechanisms are examined with our theoretical models. This aids the understanding of frequency, intensity and phase noise characteristics of frequency microcombs towards the precision limits.

The degenerate mode interaction can possess a clear avoided mode crossing to manipulate the cavity mode spectra by a mode-splitting process under a strong mode-coupling condition in high-Q microresonators. Here, the mode splitting strength can be changed by controlling the pump-resonance effective detuning in a dispersion-managed Si3N4 microresonator through a differential thermo-optic effect. The splitting mode can locally facilitate the frequency matching in normal dispersion microresonators so that the tunable parametric oscillation can be observed by tuning pump-resonance detuning. A broadly tunable THz wave radiation is generated after injecting the tunable parametric oscillation into a bias-free photomixer at room temperature.

Precise positioning of single quantum dots (QDs) in photonics crystal (PhC) cavities with nanometer-scale accuracy offers great promise for on-chip integrated quantum photonic circuit. In such coupled QD-cavity system, the decoherence fundamentally affects the coherent control for quantum communication and information processing. However, accessing to the strong-coupling regime and the impact of pure dephasing in such system have been rarely reported yet. Here, relying on our unique site-controlled pyramidal InGaAs/GaAs QDs – high-Q-PhC cavities platform, we investigate the cavity quantum electrodynamics towards strong-coupling regime mediated by pure dephasing. We demonstrate the anti-crossing and mutual linewidth narrowing of the single excitonic emission strongly coupled to cavity mode near resonance. We further present the signatures of Rabi-like oscillation and quantum beating between upper and lower branch of polariton.

We propose a method for neuron-like spiking generation using silicon microcavities, where the spiking speed is about 4 nanosecond and a million times faster than biological neurons. Both experiments and theories were carried out.

We demonstrate the steep EO tunability of four-wave-mixing (FWM) in a graphene bipolar-junction-transistor heterogeneous D-shaped fiber (GhDF). This enables the GhDF ultrasensitive to external molecule adsorption/desorption in vacuum, achieving individual gas molecule detections.

Here we present a full study and characterization of our fabricated precision optomechanical accelerometer with an 8.2 µg/Hz1/2 VRW and 50.9 µg/Hz bias stability, with innovative RF readout, suitable for inertial applications.

Leveraging the avoid mode couplings in microsphere resonators, we demonstrated fast soliton slingshot intracavity. Its soliton access range reaches 8 GHz, with success possibility > 90% and single soliton ratio > 60%.

We demonstrate a pulsed-coherent lidar system with a microresonator generated optical frequency comb which achieves sub-10μm precision and 30-μm INLMax with a 5-MSa/s sampling rate.

By using a 980 nm control laser to excite the erbium doped microsphere resonators, we realized remarkable soliton access range enhancement and counter-propagating dual-soliton manipulation, including fast on-off switch (7MHz) and beat note tuning (up to 52 kHz/mW).

We present ultra-precision distance measurement based on spectral interferometer via single soliton microcomb generated in Si3N4 microresonator. We demonstrate 3-nm repeatability over a 23-mm non-ambiguity range via homodyne interferometry, over 1000s long-term stability.

We experimentally demonstrate a chip-scale polarization to spatial-momentum qubit SWAP gate. High fidelity of the SWAP gate operation is confirmed by quantum state tomography, with average gate fidelity up to 97.30%.

We report the first high-dimensional energy-time entanglement distribution with a singly-resonant biphoton frequency comb, demonstrating time-frequency Franson interferences with high visibility, and establishing a high-dimensional entanglement link.

Broadly tunable THz radiation is generated at room temperature after injecting the tunable optical parametric oscillation emitted from a microresonator into a bias-free photomixer. The radiated THz wave features Hz-level linewidth and frequency stability.

We examine the 1325 nm T center transitions and an unknown color center with 1312 nm transitions in ion-implanted bulk Silicon and Silicon-on-insulator. We aim to use it for strong coupling via photonic crystal cavities.

We present the theoretical formulation of the fundamental limits for force sensing in optomechanical accelerometers, and matched them into the design space. Finally, we analyze the performance of a fabricated device closely approaching this bounds.

We experimentally demonstrated high-dimensional quantum key distribution with wavelength-multiplexed time-bin encoding, with photon information efficiency up to 4.082 secure-key bits/photon and secure-key rate up to 237-kbit/s. Security will be verified with dual-basis Franson interferometers.

We characterized the phase jitter of frequency microcomb with μrad phase resolution through fiber interferometry. The measured phase fluctuation PSD and integrated phase jitter are 2.588 mrad2/Hz at10 kHz and 0.126 rad at 100 μs.

We report state-of-the-art metasurface optical elements enabling our high-resolution full color prototype, via various combination of analytical and numerical simulations. Our prototype device has achieved FoV (>40o), high output efficiency (>1%), and 1080-pixel resolution.

We utilize a novel buffered time-lens architecture, panoramic-reconstruction temporal imaging (PARTI), to record long evolution portraits capturing the formation of rogue events. Further, we analyze the statistics of these events with regard to their persistence.

We demonstrate the controllable exciton-cavity mode interaction mediated by pure dephasing in a single site-controlled quantum dot-nanocavity system. With varying detuning, Purcell enhanced dynamics and phonon-assisted cavity feeding sequentially dominate the exciton-cavity mode interaction.

We examine and verify the mid-infrared transitions of 77Se+ deep donors in Silicon. We aim to use implanted Se ions as nuclear-spin/photon interfaces for on-chip quantum repeater structures.

Direct and temporal magnified real-time observations of the breathing soliton dynamics in a strong-coupled high-Q microcavity are reported. Temporal oscillating soliton pulse train with tunable amplitude modulation depth and relative breathing phase is observed.

We quantify high-dimensional energy-time entanglement with a filtered biphoton frequency comb. Franson interference measurements are performed, with the entanglement of formation up to 1.89 ± 0.03 ebits for a 45.32 GHz biphoton frequency comb.

The exotic properties of two-dimensional materials and heterostructures, built by forming heterogeneous multi-layered stacks, have been widely explored across several subject matters following the goal to invent, design, and improve applications enabled by these materials. Successfully harvesting these unique properties effectively and increasing the yield of manufacturing two-dimensional material-based devices for achieving reliable and repeatable results is the current challenge. The scientific community has introduced various experimental transfer systems explained in detail for exfoliation of these materials; however, the field lacks statistical analysis and the capability of producing a transfer technique enabling (i) high transfer precision and yield, (ii) cross-contamination free transfer, (iii) multi-substrate transfer, and (iv) rapid prototyping without wet chemistry. Here, we introduce a novel two-dimensional material deterministic transfer system and experimentally show its high accuracy, reliability, repeatability, and non-contaminating transfer features by demonstrating fabrication of two-dimensional material-based optoelectronic devices featuring novel device physics and unique functionality. The system paves the way toward accelerated two-dimensional material-based device manufacturing and characterization. Such rapid and material analyzing prototype capability can accelerate not only layered materials science in discovery but also engineering innovations.

We present an experimental and theoretical physical random bit (PRB) generator using the mesoscopic chaos from a photonic-crystal optomechanical microcavity with a size of ∼10µm and very low operating intracavity energy of ∼60 Femto-Joule that was fabricated with CMOS compatible processes. Moreover, two kinds of PRB generation were proposed with rates over gigabits per second (Gbps). The randomness of the large PRB strings was further verified using the NIST Special Publication 800-22. In addition, the Diehard statistical test was also used to confirm the quality of the obtained PRBs. The results of this study can offer a new generation of dedicated PRB solutions that can be integrated on Si substrates, which can speed up systems and eliminate reliance on external mechanisms for randomness collection.