Xiaojun Jia

Non-Hermitian physics has attracted significant interest due to its exotic phenomena. However, non-Hermitian effects at topological interfaces and their potential applications remain largely unexplored. Here, based on an interface skin-effect model, we theoretically propose a non-Hermitian topological beam splitter (NHTBS) and experimentally demonstrate it as a proof of principle in a photonic spatiotemporal lattice using coupled fiber loops. By tuning the nonreciprocal parameters of the interface lattice, we demonstrate amplification of the wave packets at the output ports of the NHTBS and achieve fully tunable splitting ratios. Moreover, we carry out 4-bit temporal beam encoding using cascaded NHTBS units and also observe the amplification phenomenon. The output ports of the encoded beam exhibit high stability even in the presence of disorder perturbations on the asymmetric interactions. This work reveals the potential of non-Hermitian interface physics for enabling future multifunctional photonic information processors.

Quantum illumination, leveraging inherent quantum correlations to maintain quantum enhancement in the lossy and noisy environment, provides a potential way for quantum radar. Although great progresses have been achieved, the distance of quantum illumination is fixed due to the employment of the fiber. In this work, the conditions of varying‐distance quantum illumination by using quantum memory are presented, where the idler beam storage can be on‐demand stored. This approach overcomes the fixed distance constraints and is tolerant to the storage noise. The quantum illumination conditions for targets at different distances can be implemented in the scenario with a controllable storage. This work offers a direct reference for potential practical applications of quantum illumination.

The Bell‐Bloom‐type optically‐pumped atomic magnetometers are well‐suited for weak geomagnetic field detection. However, conventional single‐beam pumping introduces an atomic spin polarization gradient, which limits the measurement accuracy and sensitivity. To address this issue, this paper proposes and experimentally demonstrates a Bell‐Bloom‐type rubidium FID magnetometer scheme integrating orthogonally polarized counter‐propagating pumping and multi‐pass probe detection. This design homogenizes the atomic spin polarization distribution and suppresses light shifts and power broadening. This uniform polarization, in turn, allows the five‐pass probe configuration to achieve a significantly larger signal amplitude. Experimental results reveal that, compared with the traditional single‐beam pumping and single‐pass detection scheme, the proposed magnetometer achieves a remarkable improvement in magnetic field measurement accuracy, and the magnetic field sensitivity is improved from 18.9 to 3.1 pT/. Notably, the two techniques work synergistically, yielding a 6.1‐fold sensitivity enhancement that far exceeds their individual gains. This work provides an effective technical approach and reference for optimizing the performance of atomic magnetometers and their applications in precision measurement fields.

Quantitative assessment of gigapixel whole slide images remains challenging due to morphological diversity and human intervention during slide acquisition and processing. While AI-assisted diagnostics hold promise for improving healthcare accessibility and quality, practical application is hindered by difficulties in faithfully representing histomorphological heterogeneity and scaling AI models for deployment. Prevailing approaches predominantly rely on weakly supervised algorithms based on homogeneous graph, which typically decouple diagnostic models from the underlying hardware, resulting in lack of an efficient, closed-loop, end-to-end system. Here, we propose a portable integrated system: the Intelligent Pathology Whole-Slide Analyzer (iPathWS analyzer), which embeds a Spectral Heterogeneity Engine Network and interfaces directly with a slide scanner to form a unified platform for WSI inference. The system seamlessly overlays explainable heatmaps onto slides, enabling intuitive AI integration into routine clinical workflows in a closed-loop manner. We validate the effectiveness of the iPathWS analyzer across four distinct classification tasks spanned by three independent pathology datasets, including multi-center crossover studies. Furthermore, the model produces highly detailed and interpretable heatmaps capable of detecting tiny lesions with the size of 188.5× 280.2μm², which are often imperceptible by human observers. Overall, the iPathWS Analyzer demonstrates consistent and substantial improvements in diagnostic performance, offering a scalable and robust platform for next-generation computer-aided pathology.

We propose a novel anti‐twig edge in the honeycomb lattice (HCL) that supports two symmetric high‐energy edge states. It is different from the twig edge supporting the zero‐energy flat band. Moreover, multiple flat bands are produced by applying a strain to the HCL with a twig edge or an anti‐twig edge, and the suppression or enhancement of the high‐energy edge state is observed. Under the edge‐parallel stretch strain, the high‐energy edge state band merges into the bulk band, suppressing the high‐energy edge state, whereas the zero‐energy edge state becomes delocalized. On the other hand, under the action of the edge‐parallel compression strain, both the high‐energy and zero‐energy edge states exhibit strong localization. Pseudo‐topological protection of the high‐energy edge state is explored too. Finally, by reconstructing the anti‐twig edge in the HCL, degenerate flat bands and strain‐induced multiple flat bands are produced, and topologically protected vacated anti‐twig edge states are demonstrated.

We demonstrate a compact hybrid laser cavity that enables dynamic impedance matching via polarization control, which achieves high-power, narrow-linewidth, and widely tunable near-infrared (NIR) laser emission. By rotating the nonlinear crystal to distribute the parametric gain between orthogonal polarizations, low-loss intracavity oscillation for the p -polarized field and high-efficiency output for the s -polarized signal are simultaneously achieved, which resolves the inherent conflict in output coupling requirements between the Ti:sapphire population inversion and the optical parametric oscillator (OPO). At the same time, this mechanism also introduces a nonreciprocal gain to inherently suppress the backward propagation and realize the unidirectional laser operation without an optical isolator. The laser produces ns pulses tunable from 963.26 nm to 1003.32 nm. At 992 nm, it achieves a narrow linewidth of 169.5 MHz and an output power of 9.2 W under 52 W of total 532 nm pump power, which corresponds to an optical-to-optical conversion efficiency of 17.7%. This compact design operates without active mode control or external seed injection and offers a novel, to the best of our knowledge, pathway to high-performance tunable near-infrared lasers.

Quantum sensing has emerged as a promising solution for precision measurement, and distributed quantum sensing enables multiple parameters to be measured across a network. Pushing distributed quantum sensing from the single to multimodal parameters is crucial for a complete and deep understanding of a complex system. To address this challenge, we have devised a high-sensitivity distributed quantum sensing of the multimodal parameters with a continuous-variable multipartite Greenberger–Horne–Zeilinger entangled state. All the sensors are equipped with Mach–Zehnder interferometers to couple the lasers with entangled modes. In such a quantum network, not only joint but also individual measurements of radio frequency phases and amplitudes as well as ultrasonic vibration signals are achieved beyond the standard quantum limit, showcasing the quantum Fisher information of the order of 10 ¹⁶ . These results render multimodal parameters a promising contender in quantum metrology.

This paper reported a high frequency-reproducibility high-power single-longitudinal-mode (SLM) pulsed laser which was achieved by combining an etalon set, a pre-lasing process and a nonlinear optical frequency conversion (NOFC). The NOFC was used to rapidly enlarge the loss difference between the dominant mode and sub-modes. Then, the pre-lasing process was introduced before the pulse build-up to enhance the dominant-mode intensity. On this basis, an etalon set was inserted into the resonator to select a reference frequency. As a result, the frequency reproducibility between pulses was significantly improved. In the experiment, a type-I phase-matched LBO was used to introduce the NOFC. When the pre-lasing process was introduced by slightly lowering the loss induced by the Q-switch, the spectral width of the 1064 nm laser was narrowed from 32.80 pm to 14.40 pm, and the wavelength drift was improved from less than 1.20 pm to less than 0.36 pm. On this basis, the spectral width was further narrowed to 2.20 pm by improving the frequency reproducibility between pulses through employing an etalon set with thicknesses of 0.5 mm, 1 mm and 10 mm, and the wavelength drift was less than 0.07 pm.

This paper reports a method for reducing the relative intensity noise (RIN) of actively Q-switched pulsed laser by combining the relaxation oscillation (RO) and nonlinear optical frequency conversion (NOFC). When a RO is introduced by slightly lowering the diffraction loss of acousto-optic (AO) Q-switch, the initial population inversion per pulse is stabilized to a constant value by the RO process. The RIN between pulses decreases from 4.90% to 2.48% by optimizing the diffraction loss of AO Q-switch and the RO duration. On this basis, the NOFC is introduced into the cavity by a noncritical phase-matched nonlinear crystal LiB ₃ O ₅ (LBO) to further suppress the intensity fluctuation arising from different longitudinal-mode beating with random phases, and the RIN further decreases to 1.30%, corresponding to a pulse energy stability of 0.09%. This is the lowest RIN between pulses in large energy Q-switched lasers, to the best of our knowledge. The proposed method paves the way to effectively suppress the RIN of pulsed lasers, which will help us to explore what we believe to be many new physical phenomena due to their high peak power and available manipulation in time dimension.

Leveraging the intrinsic multi physics nature of ferroelectric lithium niobate, we present a multi-functional platform (LN-MFP) that seamlessly integrates photoacoustic spectroscopy, light-induced thermoelastic spectroscopy and photodetection into a single on-chip device. The proposed LN-MFP operates over a broad spectral range spanning from the visible to the mid infrared. We experimentally demonstrate trace gas detection of nitrogen dioxide, water vapor, acetylene, carbon dioxide, methane and ammonia, achieving parts-per-billion detection limits. We implement a custom packaging solution where the LN-MFP chip and a 4.6 µm quantum cascade laser chip are mounted on a printed circuit board together with transimpedance amplification, demonstrating system-level integration. Using this co-packaged module, we demonstrate carbon monoxide detection via second-harmonic measurements, outlining a clear route towards fully integrated on-chip implementations. This compact, hybrid, multi-functional architecture markedly reduces system complexity and footprint compared with conventional benchtop systems and is intrinsically compatible with the rapidly developing lithium niobate integrated photonics ecosystem. The LN-MFP provides a core sensing building block for future all-lithium-niobate spectroscopic chips for environmental monitoring, point-of-care diagnostics and on-site chemical analysis.