Vortex beams carrying orbital angular momentum (OAM) are of great significance for high-capacity communication and super-resolution imaging. However, there is a huge gap between the free-space vortices (FVs) and plasmonic vortices (PVs) on chips, and active manipulation as well as multiplexing in more channels have become a pressing demand. In this work, we demonstrate a terahertz (THz) cascaded metadevice composed of a helical plasmonic metasurface, a liquid crystal (LC) layer, and a helical dielectric metasurface. By spin-orbital angular momentum coupling and photon state superposition, PVs and FVs are generated with mode purity of over 85% on average. Due to the inversion asymmetric design of the helical metasurfaces, the parity symmetry breaking of OAM is realized (the topological charge numbers no longer occur in positive and negative pairs, but all are positive), generating 6 independent channels associated with the decoupled spin states and the near-/far- field positions. Moreover, by the LC integration, dynamic mode switching and energy distribution can be realized, finally obtaining up to 12 modes with a modulation ratio of above 70%. This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs, exhibiting promising applications in THz communication, intelligent perception, and information processing.

Personalized health services are of paramount importance for the treatment and prevention of cardiorespiratory diseases, such as hypertension. The assessment of cardiorespiratory function and biometric identification (ID) is crucial for the effectiveness of such personalized health services. To effectively and accurately monitor pulse wave signals, thus achieving the assessment of cardiorespiratory function, a wearable photonic smart wristband based on an all-polymer sensing unit (All-PSU) is proposed. The smart wristband enables the assessment of cardiorespiratory function by continuously monitoring respiratory rate (RR), heart rate (HR), and blood pressure (BP). Furthermore, it can be utilized for biometric ID purposes. Through the analysis of pulse wave signals using power spectral density (PSD), accurate monitoring of RR and HR is achieved. Additionally, utilizing peak detection algorithms for feature extraction from pulse signals and subsequently employing a variety of machine learning methods, accurate BP monitoring and biometric ID have been realized. For biometric ID, the accuracy rate is 98.55%. Aiming to monitor RR, HR, BP, and ID, our solution demonstrates advantages in integration, functionality, and monitoring precision. These enhancements may contribute to the development of personalized health services aimed at the treatment and prevention of cardiorespiratory diseases.

Optical coherence tomography angiography (OCTA) is a powerful tool for non-invasive, label-free, three-dimensional visualization of blood vessels down to the capillary level in vivo. However, its widespread usage is hindered by the trade-off between transverse sampling rate and signal-to-noise ratio (SNR). This trade-off results in either a limited field of view (FOV) to maintain sampling density or loss of capillary details to fulfil FOV requirement. It also restricts microvascular quantifications, including flow velocimetry, which typically demand higher transverse sampling rate and SNR compared with standard qualitative OCTA. We introduce spectrally extended line field OCTA (SELF-OCTA), a cost-effective imaging modality that improves transverse sampling rate and SNR through spectrally encoded parallel sampling and increased signal acquired over longer periods, respectively. In the human skin and retina in vivo, we demonstrate its advantages in achieving significantly extended FOV without sacrificing microvascular resolution, high sensitivity to slower flow without compromising FOV, and flow velocity quantification with the highest dynamic range, emphasizing that these features can be achieved with readily available and standard OCTA hardware settings. SELF-OCTA has the potential to make wide-field, high-resolution, quantitative angiographic imaging accessible to a wider population, thereby facilitating the early detection and follow-up of vascular-related diseases.

Adaptive optics (AO) has significantly advanced high-resolution solar observations by mitigating atmospheric turbulence. However, traditional post-focal AO systems suffer from external configurations that introduce excessive optical surfaces, reduced light throughput, and instrumental polarization. To address these limitations, we propose an embedded solar adaptive optics telescope (ESAOT) that intrinsically incorporates the solar AO (SAO) subsystem within the telescope's optical train, featuring a co-designed correction chain with a single Hartmann-Shack full-wavefront sensor (HS f-WFS) and a deformable secondary mirror (DSM). The HS f-WFS uses temporal-spatial hybrid sampling technique to simultaneously resolve tip-tilt and high-order aberrations, while the DSM performs real-time compensation through adaptive modal optimization. This unified architecture achieves symmetrical polarization suppression and high system throughput by minimizing optical surfaces. A 600 mm ESAOT prototype incorporating a 12×12 micro-lens array HS f-WFS and 61-actuator piezoelectric DSM has been developed and successfully conducted on-sky photospheric observations. Validations including turbulence simulations, optical bench testing, and practical observations at the Lijiang observatory collectively confirm the system's capability to maintain about λ/10 wavefront error during active region tracking. This architectural breakthrough of the ESAOT addresses long-standing SAO integration challenges in solar astronomy and provides scalability analyses confirming direct applicability to the existing and future large solar observation facilities.

Aberration-corrected focus scanning is crucial for high-precision optics, but the conventional optical systems rely on bulky and complicated dynamic correctors. Recently, Shiyi Xiao's group proposed a method using two rotating cascaded transmissive metasurfaces for adaptive aberration correction in focus scanning. The optimized phase profiles enable precise control of the focal position for scanning custom-curved surfaces. This concept was experimentally validated by two all-silicon meta-devices in the terahertz regime, paving the way for high-precision and compact optical devices in various applications.