Optical frequency combs generated in Kerr microcavities offer a promising platform for miniaturizing comb systems. While single-pump configurations have been extensively investigated, dual- and multi-pump schemes provide new degrees of freedom for precisely controlling and tailoring the comb generation dynamics and properties. Here, we demonstrate soliton breathing phenomena induced by co-propagating pumps in the auxiliary-pump-assisted microcomb generation scheme, referred to as parametric beat-driven breathers. These breathers exhibit a unique existence range and a clear dependence on breathing frequency, significantly differing from intrinsic and intermode breather solitons. We experimentally reveal the relationship between the breathing and pump frequencies and a mode-number-dependent distribution of the relative breathing depth across comb lines. Breathing enhancement phenomena triggered by avoided mode crossings are also observed. Theoretical analysis and numerical simulations based on the dual-pump Lugiato-Lefever equation agree with experimental results. Our findings not only uncover critical instability features in co-polarized dual-pump-generated microresonator soliton frequency combs but also fundamentally highlight the necessity of pump architecture optimization for achieving enhanced stability and operational performance in practical Kerr-comb-based photonic systems.

Optical frequency combs generated in high-Q microresonators have unique applications, and the precise dispersion measurement is crucial to the research and design of microresonators and the generation of optical frequency combs. Here, we demonstrate a dispersion measurement method for the high-Q microresonator assisted by a lightwave component analyzer (LCA). By scanning the modulation-sideband frequencies, LCA can determine the precise frequency separation of the microresonator resonance modes on the left and right sides of the probe light. Next, the dispersion parameters of all resonance modes in the high-Q microresonator can be obtained by varying the position of the probe light. The microresonator's dispersion parameters are also characterized using a fiber ring scheme, thereby verifying the accuracy of the LCA. The results from the two methods matched well, but the LCA method showed superior accuracy and required no additional reference frequency markers.

Electro-optic (EO) Mach-Zehnder modulators (MZMs) featuring high modulation efficiency and wide bandwidth are essential for large-capacity optical communication systems. To date, thin-film lithium niobate (TFLN) MZMs have emerged as a promising solution owing to the exceptional EO bandwidth and compactness, and thus significantly reduced capacitance. However, integrated TFLN MZMs are still several millimeters to centimeters in path length due to the limited modulation efficiency determined by the suboptimal confinement of the electric and optical fields. This limitation hinders large-scale integration for parallelization or multiplexing and prevents the economically efficient co-integration with compact electronics. Here, this challenge is overcome by merging sub-wavelength plasmonic slot waveguides with the TFLN platform to form a strong field confinement below the diffraction limit of optics, and enhance EO overlap and light-matter interactions. A record-high modulation efficiency of 0.070 V cm is demonstrated with an ultra-short length of 15 mu m. This plasmonic TFLN MZM exhibits a 3-dB EO bandwidth exceeding 110 GHz that allows for transmitting 110 Gbaud binary phase-shift keying signals with a bit error ratio of 2.5 x 10-5. This demonstrated plasmonic TFLN MZM provides a promising solution to future ultra-high-speed and large-scale photonic integrated systems for optical interconnections, optical computing, and optical sensing functions.

Ultrahigh-bandwidth, high-stability, and ultra-compact electro-optic (EO) modulators are the key components for next-generation high-speed optical communications and computing systems. Surface plasmon polaritons (SPPs) have attracted much attention for reducing the device size and accelerating the device response owing to their nanoscale field confinement below the diffraction limit. However, existing plasmonic EO modulators still have challenges in either bandwidth or stability due to the frequency-dependent permittivity or their limited thermal and photochemical stability. These limitations lead to a modulation efficiency drop-off at low frequencies due to the decrease in dielectric constant and obstruct reliable long-term operation. Here, by integrating SPPs with the lithium niobate (LN) platform, we develop an EO phase modulator with ultrahigh bandwidth, high thermal stability, and an ultra-compact footprint. This plasmonic LN phase modulator exhibits a measured ultra-flat bandwidth exceeding 110 GHz with an ultralow half-wave voltage length product of 0.081 V cm and a compact modulation length of 15 mu m. Further theoretical analysis validates a calculated 3-dB bandwidth of 184 GHz and indicates a potential 3-dB bandwidth beyond 760 GHz through optimizing the electrode pad size. Moreover, under a thermal shock of 260 degrees C, the variation of the EO modulation response is below 0.2 dB, evidencing excellent thermal reliability. This study offers a new solution for photonic integrated circuits that demand ultrahigh bandwidth, long-term reliability, and extreme integration density, with potential applications in next-generation high-speed optical communications. (c) 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license

The soaring demand for computing resources has spurred great interest in photonic computing with higher speed and larger computing capacity. Photonic logic gates are of crucial importance due to the fundamental role of Boolean logic in modern digital computing systems. However, most photonic logic schemes struggle to exhibit the capability of massively parallel processing and flexible reconfiguration, owing to weak and fixed nonlinearity in optical elements. Here, we propose a photonic logic tensor computing architecture for the first time and fabricate the photonic universal logic tensor core (PULTC) with a parallel logic computing capacity beyond TOPS. Ten wavelength channels and four spatial channels are designed in PULTC, where the logic computing speed in each channel can reach 50 Gbit/s. After the nonlinear mapping of microring modulators, arbitrary logic operations can be achieved by configuring the Mach-Zehnder interferometer mesh. Our work offers an innovative route for photonic universal logic computing with high-parallel capability and propels the practical applications of photonic logic computing.

Continuous real-time analysis of the microwave spectrum is crucial for observing and analyzing high-speed random events and short-duration transient events. However, most current schemes analyze the spectrum in real-time with gaps, which inevitably leads to the loss of some critical information. A gap-free real-time microwave spectrum analyzer based on temporal convolution is demonstrated experimentally. By leveraging the temporal overlapping of stretched pulses, the analyzer achieves a high frame rate of 233 MHz, a frequency resolution of approximate to 500 MHz, an instantaneous bandwidth (dual sidebands) of nearly 130 GHz, a 100% signal capture ratio, and a measurement accuracy better than 20 MHz. Owing to the exemplary system performance, the real-time dynamic frequency identification for different types of microwave signals covering the S-band to Q-band is demonstrated, and the frequency can be accurately identified at any given time. Furthermore, the real-time capturing of transients is also demonstrated continuously. The high-performance analyzer can open a new horizon for real-time analysis and processing of high-speed time-domain waveforms in communication, imaging, and sensing applications.

Laser-based light detection and ranging technology, a vital tool for fast long-range distance measurement, plays an essential role across both scientific and industrial fields. The conventional dual-comb ranging method is a critical player in this field with high precision. However, the Nyquist sampling theorem results in a trade-off between the measurement speed and precision, and the non-ambiguity range (NAR) is also limited by the comb cycle, which hinders the further advancement of the technology. To address these issues, dual-chirped-comb interferometry has emerged as an innovative technique that eliminates the measurement speed limitation and extends the NAR for real-time ranging. With the utilization of dual-comb and dispersive time-stretch techniques (or dispersive Fourier transform), the inherent constraint imposed by the Nyquist sampling theorem is considerably alleviated, facilitating a transient distance measurement. This paper introduces the principle of dual-chirped-comb interferometry and discusses the critical factors for achieving absolute distance measurement. The advancement in speed, in comparison to the conventional dual-comb ranging method, has also been emphasized. In addition, some remarkable works and results are presented to visualize the system’s performance. Finally, this paper provides a perspective on potential future improvements and applications, such as in acoustic sensing, and explores the outlook for this emerging technology in the conclusion part.

Terahertz (THz) sensors play an essential role in terahertz sensing, and the whispering gallery mode resonator (WGMR) is one of the competitive platforms to enhance sensitivity. The traditional on-chip WGMRs are challenging with sensing degradation resulting from the deviation in practical fabrication. The adjustable THz sensor based on a silicon Mach–Zehnder interferometer-coupled microring resonator (MZI-MRR) is proposed and designed in this work. With the different heating power, the THz-MZI-MRR can be precisely switched between three coupling states with high repeatability. The maximum extinction ratio and Q are adjusted to 51.2 dB and 1322, respectively. The sensing characteristics of three different states are systematically demonstrated for the first time, exhibiting various unique capabilities. By adjusting the coupling state, the sensor maintains fantastic sensing ability in a larger measurement range. The proposed adjustable THz-MZI-MRR is suitable for complex and practical detection scenarios and should promote the prosperity of THz sensing.

Orbital Angular Momentum (OAM) lasers have potential demand in many applications such as large capacity communication systems, laser processing, particle manipulation and quantum optics. OAM mode femtosecond fiber laser has become the research focus with the advantages of simple structure, low cost and high peak power. The current OAM mode femtosecond fiber lasers have made breakthroughs in the repetition frequency, pulse width, spectrum width and other key parameters, but it is difficult to achieve good overall performance. Besides, the repetition rate is currently in tens of MHz. In this paper, a large-bandwidth mode coupler is made based on the mode phase matching principle. Among them, the first order mode coupler with 3dB polarization dependent loss is made by the technology of strong fused biconical taper, and the second order mode coupler with 0.3dB polarization dependent loss is made by the technology of weak fused biconical taper. Combined with the nonlinear polarization rotation mode-locking mechanism, OAM mode femtosecond fiber lasers with over 100 MHZ repetition rate are built. The achievement of the key parameters is attributed to the selection of dispersion shifted fibers that can accurately adjust intracavity dispersion. Compared to traditional dispersion compensation fibers (DCF), the group velocity dispersion is reduced by an order of magnitude, so it can better adjust intracavity dispersion to achieve the indicators of large spectral bandwidth and narrow pulse width. In addition, the diameter of the fiber is 8μm, which is the same as that of a single mode fiber. Compared to DCF, the fusion loss can be ignored, so only a shorter gain Erbium-doped fiber is required that ensure a shorter overall cavity length and achieve high repetition frequency. The experimental results show that the first order OAM mode fiber laser has 113.6 MHz repetition rate, 98 fs half-height full pulse width, and 101nm 10-dB bandwidth. Second-order OAM mode fiber laser has 114.9 MHz repetition rate, 60 fs half-height full pulse width, and 100nm 10-dB bandwidth. Compared with the reported schemes, our scheme has better performance in key parameters such as repetition rate, pulse width and spectral width. We believe that the OAM mode fiber laser with good over performance is expected to be more widely used in OAM communication, particle manipulation and other research fields.

An ultra-compact lithium niobate phase modulator based on the plasmonic slot waveguide is demonstrated with a length of ~16 μm, featuring a bandwidth exceeding 110 GHz and a high-rate operation beyond 90 Gbaud.

Optical computing has shown immense application prospects in the post-Moore era. However, as a crucial component of logic computing, the digital multiplier can only be realized on a small scale in optics, restrained by the limited functionalities and inevitable loss of optical nonlinearity. In this paper, we propose a time-space multiplexed architecture to realize large-scale photonic-electronic digital multiplication. We experimentally demonstrate an 8×2-bit photonic-electronic digital multiplier, and the multiplication with a 32-bit number is further executed at 25 Mbit/s to demonstrate its extensibility and functionality. Moreover, the proposed architecture has the potential for on-chip implementation, and a feasible integration scheme is provided. We believe the time-space multiplexed photonic-electronic digital multiplier will open up a promising avenue for large-scale photonic digital computing.

Low-cost, small-sized, and easy integrated high-performance photodetectors for photonics are still the bottleneck of photonic integrated circuits applications and have attracted increasing attention. The tunable narrow bandgap of two-dimensional (2D) layered molybdenum ditelluride (MoTe2) from similar to 0.83 to similar to 1.1 eV makes it one of the ideal candidates for near-infrared (NIR) photodetectors. Herein, we demonstrate an excellent waveguide-integrated NIR photodetector by transferring mechanically exfoliated 2D MoTe2 onto a silicon nitride (Si3N4) waveguide. The photoconductive photodetector exhibits excellent responsivity (R), detectivity (D*), and external quantum efficiency at 1550 nm and 50 mV, which are 41.9 A W-1, 16.2 x 1010 Jones, and 3360%, respectively. These optoelectronic performances are 10.2 times higher than those of the free-space device, revealing that the photoresponse of photodetectors can be enhanced due to the presence of waveguide. Moreover, the photodetector also exhibits competitive performances over a broad wavelength range from 800 to 1000 nm with a high R of 15.4 A W-1 and a large D* of 59.6 x 109 Jones. Overall, these results provide an alternative and prospective strategy for high-performance on-chip broadband NIR photodetectors.

The terahertz(THz)absorption spectrum is a powerful method to identify substances.The improvement focuses on sensitivity and recovery ability.Here,we demonstrate enhanced THz vibrational absorption spectroscopy based on an on-chip THz whispering gallery mode resonator(THz-WGMR).A THz-WGMR with high Q can store energy and enhance the interaction between the THz waves and the target substances to capture the unique absorption fingerprint information.Therefore,it possesses significant sensitivity to identify trace amounts of substances.As a proof of concept,lactose powder and glucose powder are applied to demonstrate the effectiveness of our approach in recovering fingerprint absorption spectroscopy.Compared with a straight waveguide,the high sensitivity of the THz-WGMR is illustrated.The change of the transmissivity caused by the lactose reaches 7.8 dB around 532 GHz for the THz-WGMR,while only 1.4 dB for the straight waveguide,demonstrating the state-of-the-art sensing performance in fingerprint absorption recovery.We believe the proposed integrated THz-WGMR will promote the THz identification of tiny fingerprint substances.

We demonstrate an ultra-compact and efficient lithium niobate Mach-Zehnder modulator based on plasmonic slot waveguides, featuring a bandwidth exceeding 110 GHz and an operating symbol rate of 40 Gbaud.

Despite more than 40 years of development, it remains difficult for optical logic computing to support more than four operands because the high parallelism of light has not been fully exploited in current methods that are restrained by inefficient optical nonlinearity and redundant input modulation. In this paper, we propose a large-scale optical programmable logic array(PLA) based on parallel spectrum modulation. By fully exploiting the wavelength resource, an eight-input PLA is experimentally demonstrated with 256 wavelength channels. And it is extended to nine-input PLA through the combination of wavelength's and spatial dimensions. Based on PLA, many advanced logic functions like 8-256 decoder, 4-bit comparator, adder and multiplier, and state machines are first realized in optics. We implement the two-dimensional optical cellular automaton(CA) for what we believe is the first time and run Conway's Game of Life to simulate the complex evolutionary processes(pulsar explosion, glider gun, and breeder). Other CA models, such as the replicator-like evolution and the nonisotropic evolution to generate the Sierpinski triangle are also demonstrated. Our work significantly alleviates the challenge of scalability in optical logic devices and provides a universal optical computing platform for two-dimensional CA.

The sub-THz inter-chip interconnections are first demonstrated with terahertz photomixers based on standard-process fabricated germanium-silicon photodetectors and bow-tie antennas, featuring a frequency range over 200 GHz.

With the development of high-frequency carriers and high-capacity communications, ultrahigh-speed spectrum analyzer based on all-optical methods has been demonstrated in many fields. Limited by current data processing algorithms, ultrahigh-speed spectrum analyzers based on time-lens, such as frequency-domain light intensity spectrum analyzer (f-LISA) and parametric spectro-temporal analyzer (PASTA), are not yet to automatically process acquired data, which hinders their practicality. In this paper, a frame segmentation algorithm based on time-domain waveform analysis is proposed to achieve the automatic data processing of these analyzers, which can directly generate the spectro-temporal image of the signal under test. In a single-soliton test based on the f-LISA platform, the algorithm achieves an accuracy of 93.28% when the soliton changes and 90.04% when the soliton is stable. And in this test, the single-frame processing time of the algorithm is 419us. We believe the proposed algorithm will facilitate the practical application of spectrum analyzers like f-LISA and PASTA and provide a reference for other real-time measurement schemes.

We demonstrate an ultra-compact and high-efficiency lithium niobate Mach-Zehnder modulator enabled by two vertical plasmonic slot waveguides, which shows a half-wave voltage-length product of 0.042 Vcm and a theoretical bandwidth exceeding 1.4 THz.