arXiv subjects

Jiejun Zhang

Publications and source records attributed to Jiejun Zhang.

9 recordsLinked to original sources

arXiv2026

Integrated Microwave Photonics: From Material Platforms to Systems-on-Chip

In this paper, recent advances in integrated microwave photonics (IMWP) are reviewed, including material platforms, integration technologies, and system functionalities. Emerging opportunities and future perspectives are discussed. Silicon (Si) and silicon nitride (SiN) provide dense routing, programmable filtering, and low-loss delay; indium phosphide (InP) supplies optical gain, light generation, and high-speed photodetection; thin-film lithium niobate (TFLN) offers linear and broadband electro-optic conversion; and photonic integration is emerging as a practical path to synergize complementary capabilities. Recent work shows a marked shift from isolated modulators, filters, and delay lines toward chip- and module-level systems, ranging from signal processing engines, real-time spectrum sensing, to full-spectrum wireless links, fiber-wireless conversion, silicon beamforming, integrated radar, programmable processors, and photonic convolution engines with on-chip sources and detectors. As these demonstrations become more mature and complete, the key questions move beyond bandwidth and efficiency toward system integration, microwave packaging, calibration stability, analog link performance, and application-level validation.

physics.optics↗

arXiv2026

PRL-Bench: A Comprehensive Benchmark Evaluating LLMs' Capabilities in Frontier Physics Research

The paradigm of agentic science requires AI systems to conduct robust reasoning and engage in long-horizon, autonomous exploration. However, current scientific benchmarks remain confined to domain knowledge comprehension and complex reasoning, failing to evaluate the exploratory nature and procedural complexity of real-world research. In this work, we present research-oriented evaluations in theoretical and computational physics, a natural testbed with comprehensive domain knowledge, complex reasoning, and verifiable end-to-end workflows without reliance on experiments. Here we introduce PRL-Bench (Physics Research by LLMs), a benchmark designed to systematically map the capability boundaries of LLMs in executing end-to-end physics research. Constructed from 100 curated papers from the latest issues of Physical Review Letters since August 2025 and validated by domain experts, PRL-Bench covers five major theory- and computation-intensive subfields of modern physics: astrophysics, condensed matter physics, high-energy physics, quantum information, and statistical physics. Each task in the benchmark is designed to replicate the core properties of authentic scientific research, including exploration-oriented formulation, long-horizon workflows, and objective verifiability, thereby reconstructing the essential reasoning processes and research workflows of real physics research. Evaluation across frontier models shows that performance remains limited, with the best overall score below 50, revealing a pronounced gap between current LLM capabilities and the demands of real scientific research. PRL-Bench serves a reliable testbed for accessing next generation AI scientists advancing AI systems toward autonomous scientific discovery.

cs.LG↗

arXiv2025

PhysMaster: Building an Autonomous AI Physicist for Theoretical and Computational Physics Research

Advances in LLM reasoning and tool use have enabled agentic science, yet frontier theoretical and computational physics remains challenging because research requires deep domain expertise, long-horizon reasoning, and reliable numerical computation. We introduce PRL-Bench, a research-reproduction benchmark adapted from 100 Physical Review Letters papers across major areas of modern physics. PRL-Bench distills realistic research workflows into traceable tasks with explicit intermediate artifacts and diverse evaluation rubrics; each task is estimated by domain experts to require more than six hours for a specialized PhD student to reproduce independently. Evaluations show that existing agents remain unreliable on extended research workflows. We therefore present PhysMaster, a scientific agent combining adaptive MCTS-based multi-trajectory exploration with hierarchical memory to improve long-horizon robustness and knowledge accumulation. PhysMaster achieves the highest overall PRL-Bench score of 51.08, outperforming Codex, OpenHands, OpenClaw, and ReAct, and yields relative improvements of 14.13 percent to 93.38 percent across backbone models. Error analysis shows that PhysMaster substantially reduces failures from incomplete long-horizon execution, while remaining bottlenecks lie in physics knowledge and analytical reasoning. Together, PRL-Bench and PhysMaster provide a rigorous benchmark and effective system for advancing autonomous AI research in frontier physics.

cs.AI↗

arXiv2025

Synergistic Antenna-Modulator Integration for Monolithic Photonic RF Receiver

Integrated radio-frequency (RF) photonics plays a pivotal role in wireless communications, sensing, and radar due to its large intrinsic bandwidth, remote distribution capability, and compact footprint. However, despite significant advances in photonic integrated circuits (PICs), the practical deployment of these systems remains constrained by the bulky nature of essential RF components (e.g., bulky antennas, amplifiers, and cables), especially in covert, conformal, and space-constrained applications. To overcome these limitations, monolithic electronic-photonic integrated circuits (EPICs), enabling miniaturized and synergistic integration of both RF and photonic components, are gaining notable attention. As a groundbreaking advancement, we demonstrate a novel photonic RF receiver that monolithically integrates a bow-tie antenna and a microring modulator on a thin-film lithium niobate platform. The chip innovatively leverages dual-resonance enhancement mechanism, RF resonance from the antenna and optical resonance from the microring, to significantly boost the RF-to-optical conversion efficiency. A record-high figure of merit (FOM) of 3.88 W-1/2 is achieved within a compact footprint of 2*1.7 mm2. As the first demonstrations, the integrated receiver is deployed in an integrated sensing and communication (ISAC) system, achieving centimeter-level radar ranging accuracy and 3.2 Gbps wireless communication capacity, as well as real-time video transmission function in moving scenarios. This seminal work paves a new way for covert, conformal, and miniaturized frontends in wireless communication and sensing applications, including body area networks, unmanned aerial vehicles, high-speed vacuum maglevs, and electronic warfare systems.

physics.optics↗

arXiv2025

Microwave Photonics for Space-Ground Connectivity

Future space-ground communication networks require a seamless fusion of technologies that combine the all-weather reliability of microwave links with the ultra-high data capacity of near-infrared optical systems. Achieving this vision demands compact, robust, and multifunctional hardware, yet monolithic integration of these fundamentally distinct domains has remained elusive. Here, we present the first monolithically integrated silicon photonic chip that bridges microwave and optical domains for dual-band free-space communications and dynamic beamforming. The chip integrates a microwave true time delay (TTD) beamforming network, an optical phased array (OPA) beamforming network, and an optical coherent transceiver, all on a silicon-on-insulator (SOI) platform. By uniting the strengths of microwave resilience, optical bandwidth, and coherent detection sensitivity, this photonic integrated circuit represents a critical step toward reconfigurable, interference-resistant, high-throughput links for satellites, UAVs, and ground stations. Experimental demonstrations confirm two-dimensional dynamic beam steering in both bands 24.9 deg x 18.5 deg at microwave frequencies and 10 deg x 4.7 deg in the optical domain. In a 5-meter free-space link, the chip achieves error-free transmission at 10 Gbps for microwave and 80 Gbps per wavelength in the near infrared band. These results establish integrated microwave photonics as a promising platform for bridging Earth and orbit through compact, dual-band, beamforming-enabled transceivers.

physics.optics↗

arXiv2025

Fostering cultural change in research through innovative knowledge sharing, evaluation, and community engagement strategies

Bringing together researchers, funders, industry partners, and publishers from 14 countries across 5 continents, we advance the debate around open-science, assessment and learning. We introduce an integrative "open knowledge system" framework linking knowledge production, validation, assessment, and reuse into one ecosystem view, and translate it into actionable recommendations for each stakeholder. Shifting focus to modular, machine-readable knowledge objects, these recommendations are intended to help diagnose misaligned incentives and guide reforms that properly value all scientific contributions.

cs.SI↗

arXiv2025

A photonic integrated processor for multiple parallel computational tasks

Optical networks with parallel processing capabilities are significant in advancing high-speed data computing and large-scale data processing by providing ultra-width computational bandwidth. In this paper, we present a photonic integrated processor that can be segmented into multiple functional blocks, to enable compact and reconfigurable matrix operations for multiple parallel computational tasks. Fabricated on a silicon-on-insulator (SOI) platform, the photonic integrated processor supports fully reconfigurable optical matrix operations. By segmenting the chip into multiple functional blocks, it enables optical matrix operations of various sizes, offering great flexibility and scalability for parallel computational tasks. Specifically, we utilize this processor to perform optical convolution operations with various kernel sizes, including reconfigurable three-channel 1x1 convolution kernels and 2x2 real-valued convolution kernels, implemented within distinct segmented blocks of the chip. The multichannel optical 1x1 convolution operation is experimentally validated by using the deep residual U-Net, demonstrating precise segmentation of pneumonia lesion region in lung CT images. In addition, the capability of the 2x2 optical convolution operation is also experimentally validated by constructing an optical convolution layer and integrating an electrical fully connected layer, achieving ten-class classification of handwritten digit images. The photonic integrated processor features high scalability and robust parallel computational capability, positioning it a promising candidate for applications in optical neural networks.

physics.optics↗

arXiv2022

Tera-sample-per-second arbitrary waveform generation in the synthetic dimension

The synthetic dimension opens new horizons in quantum physics and topological photonics by enabling new dimensions for field and particle manipulations. The most appealing property of the photonic synthetic dimension is its ability to emulate high-dimensional optical behavior in a unitary physical system. Here we show that the photonic synthetic dimension can transform technical problems in photonic systems between dimensionalities, providing unexpected solutions to technical problems that are otherwise challenging. Specifically, we propose and experimentally demonstrate a photonic Galton board (PGB) in the temporal synthetic dimension, in which the temporal high-speed challenge is converted into a spatial fiber-optic length matching problem, leading to the experimental generation of tera-sample-per-second arbitrary waveforms. Limited by the speed of the measurement equipment, waveforms with sampling rates of up to 341.53 GSa/s are recorded. Our proposed PGB operating in the temporal synthetic dimension breaks the speed limit in a physical system, bringing arbitrary waveform generation into the terahertz regime. The concept of dimension conversion offers possible solutions to various physical dimension-related problems, such as super-resolution imaging, high-resolution spectroscopy, time measurement, etc.

physics.optics↗

arXiv2019

Parity-time symmetry in wavelength space with spatial singularity

Implementation of a parity-time (PT) symmetric microwave photonic system in the optical wavelength space with spatial singularity is proposed. In the proposed PT-symmetric microwave photonic system, the gain and loss modes are confined in a single spatial resonator, which is different from a conventional PT-symmetric system in which the two modes are localized in two physically separated resonators to form one-dimensional spatial potential symmetry as required by the simplest one-dimensional parity transformation. We show that PT-symmetry can be implemented between subspaces in non-spatial parameter spaces, in which the gain and loss modes can perfectly overlay spatially but are distinguishable in the designated parameter space. The resultant spatial singularity enables the possibility in implementing PT-symmetric systems with increased structural simplicity, integration density and long-term stability. To prove the concept, a PT-symmetric optoelectronic oscillator (OEO) in the optical wavelength space is implemented. The OEO has a single-loop architecture, with the gain and loss microwave modes carried by two optical wavelengths to form two mutually coupled wavelength-space resonators (WSRs). PT-symmetry is achieved by controlling the wavelength spacing and the power contrast. The operation of PT symmetry in the OEO is verified by the generation of a 10-GHz microwave signal with a low phase noise of 129.3 dBc/Hz at 10-kHz offset frequency and a high sidemode suppression ratio (SMSR) of 66.22 dB. Compared with a conventional spatial PT-symmetric system, one in the wavelength space features a much simpler configuration, better stability and greater resilience to environmental interferences.

physics.optics↗