We present the first demonstration of a polymer-based micro-ring resonator array with over 40 elements fabricated using nanoimprint lithography (NIL), and its application for photoacoustic tomography imaging. By precisely varying the radius of each micro-ring at the nanometer scale and maintaining its high-quality factor, we achieved distinguishable resonances within a free spectral range of only 2.19 nm. The micro-ring array was used to perform photoacoustic tomography (PAT), achieving lateral and axial resolutions of 40 µm and 38 µm, respectively, and an ultrasound response bandwidth of 173.5 MHz, and a noise equivalent pressure (NEP) of 13.5 Pa. PAT images of ex vivo mouse prostates were acquired by the micro-ring array, showing a high correlation with biological tissue structures and regions of blood vessels. Further spectral analysis of the PAT images can differentiate the prostate cancers from the normal prostates. This work highlights the significant advantages of using NIL-fabricated micro-ring resonator arrays made from polymer materials, demonstrating their potential for advanced applications in biomedical imaging as well as optical communications and integrated photonic systems.

Unveiling the vacancy oscillation mode in amorphous binary oxides films at nanoscale and its impact on ionic conductivity and conductivity spectra is vital to explore the tightly intertwined connection between reversible oxygen migration and stabilizing and controlling the ferroelectric behavior, to complement traditional ferroelectric doped-HfO₂ materials. Using terahertz time-domain spectroscopy (THz-TDS), infrared reflection spectra, and density functional theory (DFT) calculations, we investigate the optical absorption and reflection spectra of crystalline and amorphous ZrO₂ thin film by varying oxygen vacancy concentrations. Experimental results show that oxygen vacancy migration rather than intrinsic paraelectric nature in films significantly affect the conductivity and polarization behavior of ZrO₂ thin film. Notably, except for the phonon modes induce distinct absorption peaks around 11 THz, additional absorption peaks are observed in the 1–2 THz range, which are caused by localized states originated from the oxygen vacancies, supported by DFT calculations. Temperature-dependent ion migration behavior further confirms the role of vacancy oscillation modes in ionic conductivity. DFT calculations additionally reveal how oxygen vacancies alter infrared absorption and optical modes, leading to a redshift in existing absorption peaks or the introduction of new peaks. Our findings unambiguously clarify the oxygen voltammetry characteristics in amorphous ferroelectric binary oxides films. Furthermore, the strategic deployment of amorphous binary oxides films enables the use of low-temperature atomic layer deposition (ALD) growing process, effectively alleviating routing congestion of ferroelectric oxides and offering additional design flexibility for future memory devices with ultra-low effective oxide thickness (EOT) and low thermal budget, and providing alternative technological routes that are poised to propel the development of next-generation more compact ferroelectric devices for advanced process nodes.

Sorting and detection of enantiomers hold critical importance in biomedical, chemical, and pharmacological sciences due to their fundamental role in molecular interactions and therapeutic efficacy. Over the past two decades, diverse chemical, biophysical, and microfluidic methodologies have been developed for chiral enantiomer sorting and detection. While these approaches have demonstrated significant capabilities, optical techniques have attracted increasing interest due to their intrinsic advantages, including rapid analysis, minimal sample consumption, and non-invasive operation. This review comprehensively overviews recent advances in optical methods for chiral enantiomer sorting and detection. We focus on emerging optical concepts, including exotic optical forces and engineered light fields, such as bound states in the continuum and metasurfaces, and analyze their operational principles, capabilities, and inherent limitations. Furthermore, we investigate the growing impact of artificial intelligence in reshaping optical sorting and sensing strategies, particularly its role in improving analytical precision and enabling autonomous operation. The review concludes with a forward-looking perspective, discussing persistent challenges like system scalability and real-world implementation while outlining promising future directions, including integrated lab-on-chip platforms and advanced chiral metamaterials.

Indirect X-ray imaging is an indispensable non-destructive testing technology in the medical and industrial fields. However, its quality is restricted by the light output and optical crosstalk of the scintillation screens. Herein, we report a series of hafnium-based organic-inorganic metal halides (OIMHs) with regulated organic cation chain lengths. The thermally activated delayed fluorescence (TADF) is demonstrated in these materials by their anti-thermal quenching luminescence characteristics, fitting of temperature-dependent photoluminescence decay lifetime, and a series of theoretical calculations. These represent non-luminescent triplet excitons that can be emitted by reverse intersystem crossing (RISC), thus improving the utilization rate of excitons and increasing the light output of scintillators. The highest performance of our reported hafnium-based OIMHS shows a light yield of 56563.31±1250 photons/MeV and detection limit of 23.86 nGy_air/s. Moreover, the optical crosstalk is suppressed by developing silicon array scintillation screens, and an ultra-high spatial resolution of 31.41 lp/mm is achieved. These results offer insights into the luminescent mechanism of hafnium-based OIMHs and initiate a new paradigm for exciton-optical co-management for high-quality X-ray imaging.

Investigating the composition ratio of ethanol–water molecular clusters in air, which are responsible for anisotropic behavior, is a significant challenge, primarily owing to the difficulty of detecting Rayleigh scattering, an inherently weak signal highly susceptible to external interference. This study overcame these limitations by integrating laser diffraction focusing with artificial neural networks. We demonstrate a fully non-contact sensing system that circumvents the direct measurement of difficult-to-distinguish Rayleigh scattering signals. Our approach infers ethanol content by utilizing a self-fabricated multi-layered graphene Fresnel lens. An analysis of gaseous ethanol content in the 0.01%–0.1% range revealed that while a wavelength of 405 nm exhibited high sensitivity with up to a 7% intensity change corresponding to ethanol content, a wavelength of 638 nm provided superior stability for deep-learning analysis as its intensity parameter remained fixed. Ultimately, by combining the 638 nm laser with our self-developed self-aware assembly network model, we successfully inferred ethanol content with an R² of 0.884, even under varied power conditions. This study creates a new path for recognizing weak Rayleigh scattering signals that were previously difficult to measure and may facilitate the development of rapid and durable sensing systems, such as for the non-invasive diagnosis of gas molecules.

The notion of a path in quantum mechanics has fuelled many debates on the very nature of what quantumness is. Although traditionally associated with physical paths, such as double slits, it can be far more abstract. Now Yan Wang and colleagues demonstrate exotic trajectories in an abstract quantum space built from the Bloch sphere of a locally entangled photon, while shaping the path using its non-local entangled partner as a control. The steering and directing along these new paths is enabled by cascaded metasurfaces, demonstrating the myriad of possibilities that emerge when structured matter meets quantum structured light.