Selective Excitation of Exciton-Polariton Condensate Modes in an Annular Perovskite Microcavity.

Exciton-polariton systems composed of a light-matter quasi-particle with a light effective mass easily realize Bose-Einstein condensation. In this work, we constructed an annular trap in a halide perovskite semiconductor microcavity and observed the spontaneous formation of symmetrical petal-shaped exciton-polariton condensation in the annular trap at room temperature. In our study, we found that the number of petals of the petal-shaped exciton-polariton condensates, which is decided by the orbital angular momentum, is dependent on the light intensity distribution. Therefore, the selective excitation of perovskite microcavity exciton-polariton condensates under all-optical control can be realized by adjusting the light intensity distribution. This could pave the way to room-temperature topological devices, optical cryptographical devices, and new quantum gyroscopes in the exciton-polariton system.

Lab-on-Device Synthesis of Hierarchical Macro/Mesoporous WO3 Semiconducting Films for High-Performance H2S Sensing.

The performance consistency of the gas sensor is strongly dependent on the interface binding between the sensitive materials and the electrodes. Traditional powder coating methods can inevitably lead to differences in terms of substrate-film interface interaction and device performance, affecting the stability and lifetime. Thus, efficient growth of sensitive materials on device substrates is crucial and essential to enhance the sensing performance, especially for stability. Herein, hierarchically ordered macro/mesoporous WO3 films are in situ synthesized on the electrode via a facile soft/hard dual-template strategy. Orderly arrayed uniform polystyrene (PS) microspheres with tailored size (ca. 1.2 µm) are used as a hard template, and surfactant Pluronic F127 as a soft template can co-assemble with tungsten precursor into ordered mesostructure in the interstitials of PS colloidal crystal induced by solvent evaporation. Benefiting from its rich porosity and high stability, the macro/mesoporous WO3-based sensor shows high sensitivity (Rair/Rgas = 307), fast response/recovery speed (5/9 s), and excellent selectivity (SH2S/Smax > 7) toward 50 ppm H2S gas (a biomarker for halitosis). Significantly, the sensors exhibit an extended service life with a negligible change in sensing performance within 60 days. This lab-on-device synthesis provides a platform method for constructing stable nanodevices with good consistency and high stability, which are highly desired for developing high-performance sensors.

Coherent detection of the rotational Doppler effect measurement based on triple Fourier transform.

In recent years, the rotational Doppler effect (RDE) has been widely used in rotational motion measurement. However, the performance of existing detection systems based on the RDE are generally limited by the drastic reduction of signal-to-noise ratio (SNR) due to the influence of atmospheric turbulence, partial obscuration of the vortex beam (VB) during propagation, and misalignment between the optical axis of VB and the rotational axis of the object, which poses a challenge for practical applications. In this paper, we proposed a coherent detection method of the RDE measurement based on triple Fourier transform. First, the weak RDE signal in backscattered light is amplified by using the balanced homodyne detection method, and the amplified signal still retains the same characteristic of severe broadening in the frequency domain as the original signal. Furthermore, we proposed the triple Fourier transform to extract the broadened RDE frequency shift signal after the coherent amplification. The proposed method significantly improves the SNR of RDE measurement and facilitates the accurate extraction of rotational speed, which helps to further improve the RDE detection range and promote its practical application.

Sorting infrared optical vortices with a nonlinear angular lens.

Analogous to the regular lens, which spatially maps plane waves in the space domain to distinct points in the Fourier domain, the angular lens establishes the mapping relations between an angular mode and angular position, thus providing an effective toolkit for detecting an optical vortex. However, using the angular lens to sort infrared optical vortex modes via nonlinear optical processes remains relatively unexplored. Here, we design a nonlinear optical version of the angular lens to map the various infrared optical vortex modes to different angular positions in the visible region. We successfully sort nine infrared optical vortex modes of different topological charges with a visible camera, showing the cost-effective ability to sort infrared vortices compared to a relatively expensive infrared camera. Our scheme holds promise for infrared remote sensing, infrared vortex-encoded optical communications, and so on.

Microglia-mediated drug substance transfer promotes chemoresistance in brain tumors: insights from an in vitro co-culture model using GCV/Tk prodrug system.

BACKGROUND: It is well known that tumor-associated macrophages (TAMs) play essential roles in brain tumor resistance to chemotherapy. However, the detailed mechanisms of how TAMs are involved in brain tumor resistance are still unclear and lack a suitable analysis model. METHODS: A BV2 microglial cells with ALTS1C1 astrocytoma cells in vitro co-culture system was used to mimic the microglia dominating tumor stroma in the tumor invasion microenvironment and explore the interaction between microglia and brain tumor cells. RESULTS: Our result suggested that microglia could form colonies with glioma cells under high-density culturing conditions and protect glioma cells from apoptosis induced by chemotherapeutic drugs. Moreover, this study demonstrates that microglia could hijack drug substances from the glioma cells and reduce the drug intensity of ALTS1C1 via direct contact. Inhibition of gap junction protein prevented microglial-glioma colony formation and microglia-mediated chemoresistance. CONCLUSIONS: This study provides novel insights into how glioma cells acquire chemoresistance via microglia-mediated drug substance transferring, providing a new option for treating chemo-resistant brain tumors.

Gut-Derived Trimethylamine N-Oxide Promotes CCR2-Mediated Macrophage Infiltration in acute kidney injury.

BACKGROUND: Inflammation is crucial in the development of AKI and subsequent CKD following renal ischemia-reperfusion (IR) injury. Gut microbiota metabolites trigger inflammation and affect IR-induced renal damage. Yet, the driving factors and mechanisms are unclear. Trimethylamine N-oxide (TMAO), a gut-derived choline metabolite, is a strong pro-inflammatory factor that increases in patients with AKI and CKD. We hypothesized that TMAO can promote renal injury caused by IR. METHODS: Mice subjected to unilateral renal IR to induce AKI and CKD were fed a high-choline diet to observe the effects of TMAO on kidney inflammation, fibrosis, and macrophage dynamics. RESULTS: A choline-rich diet altered the gut microbiota and elevated TMAO levels, which exacerbated IR-induced AKI and subsequent CKD. Single-cell analysis identified a distinct subset of CCR2+ macrophages derived from monocytes as key responders to TMAO, intensifying immune cell interactions and worsening renal injury. TMAO promoted sustained CCR2 expression after IR, increasing macrophage infiltration. CCR2 deletion and antagonist RS-102895 improved TMAO-induced inflammation and fibrosis, alleviated renal injury induced by IR. CONCLUSIONS: Our study provides valuable insights into the link between TMAO and IR-incited renal inflammation and fibrosis, emphasizing the critical role of TMAO-mediated macrophage infiltration via CCR2 as a key therapeutic target in the acute and chronic phase after IR.

Disruption of a self-amplifying catecholamine loop reduces cytokine release syndrome.

Cytokine release syndrome (CRS) is a life-threatening complication of several new immunotherapies used to treat cancers and autoimmune diseases1-5. Here we report that atrial natriuretic peptide can protect mice from CRS induced by such agents by reducing the levels of circulating catecholamines. Catecholamines were found to orchestrate an immunodysregulation resulting from oncolytic bacteria and lipopolysaccharide through a self-amplifying loop in macrophages. Myeloid-specific deletion of tyrosine hydroxylase inhibited this circuit. Cytokine release induced by T-cell-activating therapeutic agents was also accompanied by a catecholamine surge and inhibition of catecholamine synthesis reduced cytokine release in vitro and in mice. Pharmacologic catecholamine blockade with metyrosine protected mice from lethal complications of CRS resulting from infections and various biotherapeutic agents including oncolytic bacteria, T-cell-targeting antibodies and CAR-T cells. Our study identifies catecholamines as an essential component of the cytokine release that can be modulated by specific blockers without impairing the therapeutic response.

A Randomized, Controlled Trial of Continuous Heparin Infusion to Prevent Asymptomatic Catheter-Related Thrombosis at Discharge in Infants After Cardiac Surgery: The CHIP-CRT Trial.

OBJECTIVES: There are conflicting results in preventing catheter-related thrombosis (CRT). Continuing infusion of unfractionated heparin (UFH) was a potential option for CRT. This study was to determine the effect of continuous UFH infusion on asymptomatic CRT at discharge in infants after cardiac surgery. STUDY DESIGN: This study was a randomized, placebo-controlled, clinical trial at a single center. All infants with central venous catheters after cardiac surgery, below 3 months of age, were eligible. Stratified by CRT, infants were randomly assigned to the UFH group or the normal saline group. UFH was initiated at a speed of 10 to 15 units/kg/h for infants with CRT and 2 to 3 units/kg/h without CRT. The primary outcome was to determine the rate of CRT at discharge. The secondary outcomes included thrombosis 6 months after surgery, adverse events of UFH, and post-thrombotic symptoms. RESULTS: Due to slow recruitment during the COVID-19 pandemic, this trial was prematurely stopped. Only 35 infants were randomly assigned to the UFH or control groups. There was no statistically significant difference in CRT rate at discharge (P=0.429) and 6 months after surgery (P=1.000) between groups. All CRTs except one disappeared at discharge. No thrombosis or post-thrombotic symptom was reported at follow-up evaluation. There was no difference between groups in duration of thrombus (P=0.088), D dimer (P=0.412), catheter in situ days (P=0.281), and post-thrombotic syndrome (P=1.000), except for activated partial thromboplastin time (P=0.001). CONCLUSIONS: With the early stop of this trial and limited data, it is difficult to draw a definitive conclusion about the efficacy of UFH on CRT. Meanwhile, considering the data from 6 months follow-up, in this population, asymptomatic CRT might resolve with no intervention.

The mechanisms of yeast extracellular metabolites in stimulating microbial degradation of trichloroethylene: Physiological characteristics and omics analysis.

The biodegradation of Trichloroethylene (TCE) is limited by low microbial metabolic capacity but can be enhanced through biostimulation strategies. This study explored the physiological effects and potential molecular mechanisms of the yeast Yarrowia lipolytica extracellular metabolites (YEMs) on the degradation of TCE by Acinetobacter LT1. Results indicated that YEMs stimulated the efficiency of strain LT1 by 50.28%. At the physiological level, YEMs exhibited protective effects on cell morphology, reduced oxidative stress, lessened membrane damage, and enhanced energy production and conversion. Analysis of omics results revealed that the regulation of various metabolic pathways by YEMs improved the degradation of TCE. Furthermore, RT-qPCR showed that the genes encoding YhhW protein in TCE stress and YEMs stimulation groups were 1.72 and 3.22 times the control group, respectively. Molecular docking results showed that the conformation of YhhW after binding to TCE changed into a more active form, which enhanced enzyme activity. Therefore, it is speculated that YhhW is the primary degradative enzyme involved in the process of YEMs stimulating strain LT1 to degrade TCE. These results reveal how YEMs induce strain LT1 to enhance TCE degradation.

Physiological responses and molecular mechanisms of biofilm formation induced by extracellular metabolites of euglena in Pseudomonas aeruginosa LNR1 for diesel biodegradation based on transcriptomic and proteomic.

Diesel, as a toxic and complex pollutant, is one of the main components in oily wastewater, and poses serious threats to the aquatic environment and the health of organisms. Employing environmentally friendly biostimulants to enhance the metabolic functions of microorganisms is currently the optimal choice to improve the biodegradation of oil-containing wastewater efficiency. This study takes Pseudomonas aeruginosa LNR1 as the target, analyzing the physiological responses and molecular mechanisms of biofilm formation when enhanced by the extracellular metabolites of euglena (EME) for diesel degradation. The results show that EME not only induces auto-aggregation behavior of strain LNR1, forming aerobic suspended granule biofilm, but also promotes the secretion of signaling molecules in the quorum sensing (QS) system. Transcriptomic and proteomic analyses indicate that the stimulatory effect of EME on strain LNR1 mainly manifests in biofilm formation, substance transmembrane transport, signal transduction, and other biological processes, especially the QS system in signal transduction, which plays a significant regulatory role in biofilm formation, chemotaxis, and two-component system (TCS). This study collectively unveils the molecular mechanisms of biostimulant EME inducing strain LNR1 to enhance diesel degradation from different aspects, providing theoretical guidance for the practical application of EME in oily wastewater pollution control.

Enhanced Diagnostic Efficiency of Endometrial Carcinogenesis and Progression in Women with Abnormal Uterine Bleeding through Peripheral Blood Cytokine Testing: A Multicenter Retrospective Cohort Study.

Objective: This study aimed to evaluate the role of plasma cytokine detection in endometrial cancer screening and tumor progression assessment in patients with abnormal uterine bleeding. Methods: In this multicenter retrospective cohort study of 287 patients with abnormal uterine bleeding, comprehensive clinical information and laboratory assessments, including cytokines, routine blood tests, and tumor markers, were performed. Associations between the clinical indicators and endometrial carcinogenesis/progression were evaluated. The independent risk factors for endometrial cancer and endometrial cancer with deep myometrial invasion were analyzed using multivariate binary logistic regression. Additionally, a diagnostic model was used to evaluate the predictive efficacy of these identified risk factors. Results: In patients with abnormal uterine bleeding, low IL-4 and high IL-8 levels were independent risk factors for endometrial cancer (p < 0.05). Combining IL-4, IL-8, CA125, and menopausal status improved the accuracy of assessing endometrial cancer risk. The area under curve of the model is 0.816. High IL-6 and IL-8 levels were independent risk factors for deep myometrial invasion in patients with endometrial cancer (p < 0.05). Similarly, combining IL-6, IL-8, and Monocyte counts enhanced the accuracy of assessing endometrial cancer risk with deep myometrial invasion. The area under curve of the model is 0.753. Conclusions: Cytokines such as IL-4, IL-8, and IL-6 can serve as markers for monitoring endometrial cancer and its progression in women with abnormal uterine bleeding.

Genome-wide analysis of in vivo-evolved Candida auris reveals multidrug-resistance mechanisms.

Candida auris, an emerging and multidrug-resistant fungal pathogen, has led to numerous outbreaks in China. While the resistance mechanisms against azole and amphotericin B have been studied, the development of drug resistance in this pathogen remains poorly understood, particularly in in vivo-generated drug-resistant strains. This study employed pathogen whole-genome sequencing to investigate the epidemiology and drug-resistance mutations of C. auris using 16 strains isolated from two patients. Identification was conducted through Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antimicrobial susceptibilities were assessed using broth microdilution and Sensititre YeastOne YO10. Whole-genome sequencing revealed that all isolates belonged to the South Asian lineage, displaying genetic heterogeneity. Despite low genetic variability among patient isolates, notable mutations were identified, including Y132F in ERG11 and A585S in TAC1b, likely linked to increased fluconazole resistance. Strains from patient B also carried F214L in TAC1b, resulting in a consistent voriconazole minimum inhibitory concentration of 4 µg/mL across all isolates. Furthermore, a novel frameshift mutation in the SNG1 gene was observed in amphotericin B-resistant isolates compared to susceptible ones. Our findings suggest the potential transmission of C. auris and emphasize the need to explore variations related to antifungal resistance. This involves analyzing genomic mutations and karyotypes, especially in vivo, to compare sensitive and resistant strains. Further monitoring and validation efforts are crucial for a comprehensive understanding of the mechanisms of drug resistance in C. auris.

Urease-producing bacteria with plant growth-promoting ability that may tolerate and remove cadmium from aqueous solution.

Urease-producing bacteria (UPB) are widely present in soil and play an important role in soil ecosystems. In this study, 65 UPB strains were isolated from cadmium (Cd)-polluted soil around a lead-zinc mine in Yunnan Province, China. The Cd tolerance, removal of Cd from aqueous solution, production of indoleacetic acid (IAA) and plant growth-promoting effects of these materials were investigated. The results indicate that among the 65 UPB strains, four strains with IAA-producing ability were screened and identified as Bacillus thuringiensis W6-11, B. cereus C7-4, Serratia marcescens W11-10, and S. marcescens C5-6. Among the four strains, B. cereus C7-4 had the highest Cd tolerance, median effect concentration (EC50) of 59.94 mg/L. Under Cd 5 mg/L, S. marcescens C5-6 had the highest Cd removal from aqueous solution, up to 69.83%. Under Cd 25 mg/kg, inoculation with B. cereus C7-4 significantly promoted maize growth in a sand pot by increasing the root volume, root surface area, and number of root branches by 22%, 29%, and 20%, respectively, and plant height and biomass by 16% and 36%, respectively, and significantly increasing Cd uptake in the maize roots. Therefore, UPB is a potential resource for enhancing plant adaptability to Cd stress in plants with Cd-polluted habitats.

This study utilized urease-producing bacteria screened from the soil of lead zinc mining areas in Yunnan, China as the research object, enriching the microbial resources in Yunnan. In addition, this article verified the IAA production ability and cadmium removal ability of urease-producing bacteria, and screened out bifunctional urease-producing bacteria that have potential in cadmium pollution control and plant growth promotion.

Spacecraft Attitude Measurement and Control Using VSMSCSG and Fractional-Order Zeroing Neural Network Adaptive Steering Law.

In order to improve the accuracy and convergence speed of the steering law under the conditions of high dynamics, high bandwidth, and a small deflection angle, and in an effort to improve attitude measurement and control accuracy of the spacecraft, a spacecraft attitude measurement and control method based on variable speed magnetically suspended control sensitive gyroscopes (VSMSCSGs) and the fractional-order zeroing neural network (FO-ZNN) steering law is proposed. First, a VSMSCSG configuration is designed to realize attitude measurement and control integration in which the VSMSCSGs are employed as both actuators and attitude-rate sensors. Second, a novel adaptive steering law using FO-ZNN is designed. The matrix pseudoinverses are replaced by FO-ZNN outputs, which solves the problem of accuracy degradation in the traditional pseudoinverse steering laws due to the complexity of matrix pseudoinverse operations under high dynamics conditions. In addition, the convergence and robustness of the FO-ZNN are proven. The results show that the proposed FO-ZNN converges faster than the traditional zeroing neural network under external disturbances. Finally, a new weighting function containing rotor deflection angles is added to the steering law to ensure that the saturation of the rotor deflection angles can be avoided. Semi-physical simulation results demonstrate the correctness and superiority of the proposed method.

Impact of urban space on PM2.5 distribution: A multiscale and seasonal study in the Yangtze River Delta urban agglomeration.

Despite concerted efforts in emission control, air pollution control remains challenging. Urban planning has emerged as a crucial strategy for mitigating PM2.5 pollution. What remains unclear is the impact of urban form and their interactions with seasonal changes. In this study, base on the air quality monitoring stations in the Yangtze River Delta urban agglomeration, the relationship between urban spatial indicators (building morphology and land use) and PM2.5 concentrations was investigated using full subset regression and variance partitioning analysis, and seasonal differences were further analysed. Our findings reveal that PM2.5 pollution exhibits different sensitivities to spatial scales, with higher sensitivity to the local microclimate formed by the three-dimensional structure of buildings at the local scale, while land use exerts greater influence at larger scales. Specifically, land use indicators contributed sustantially more to the PM2.5 prediction model as buffer zone expand (from an average of 2.41% at 100 m range to 47.30% at 5000 m range), whereas building morphology indicators display an inverse trend (from an average of 13.84% at 100 m range to 1.88% at 5000 m range). These results enderscore the importance of considering building morphology in local-scale urban planning, where the increasing building height can significantly enhance the disperion of PM2.5 pollution. Conversely, large-scale urban planning should prioritize the mixed use of green spaces and construction lands to mitigate PM2.5 pollution. Moreover, the significant seasonal differences in the ralationship between urban spatical indicatiors and PM2.5 pollution were observed. Particularly moteworthy is the heightened association between forest, water indicators and PM2.5 concentrations in summer, indicating the urban forests may facilitate the formation of volatile compunds, exacerbating the PM2.5 pollution. Our study provides a theoretical basis for addressing scale-related challenges in urban spatial planning, thereby forstering the sustainable development of cities.

circFANCA accelerates the malignant process of OSCC by modulating miR-34a/PA28γ signaling.

OBJECTIVES: To investigate the upstream regulatory molecules of proteasomal activator 28γ (PA28γ), and explore its specific regulatory mechanism and potential clinical significance in OSCC. MATERIALS AND METHODS: qPCR was used to examine miR-34a, circFANCA and PSME3 expression. Western blotting was adopted to detect PA28γ expression. Transwell experiments were conducted to evaluate OSCC cell migration and invasion ability. FISH was used to evaluate the subcellular localization of circFANCA and miR-34a, and RNA pull-down verified the interaction between them. The expression of circFANCA and miR-34a in clinical cohorts was assessed by ISH, and the results were subjected to survival analysis using Kaplan-Meier analysis. RESULTS: Here, we proved that miR-34a expression is lower in highly aggressive OSCC tissues and cell lines. Notably, miR-34a can downregulate PA28γ expression and inhibit OSCC invasion and migration. Next, we confirmed that circFANCA promoted OSCC cell metastatic ability by sponging miR-34a. Importantly, interfering with miR-34a rescued the malignant progression of OSCC induced by silencing circFANCA. Finally, clinical data showed lower miR-34a expression and higher circFANCA expression were associated with poor prognosis in OSCC patients. CONCLUSION: The circFANCA/miR-34a/PA28γ axis facilitates the metastasis of OSCC, and circFANCA and miR-34a have potential to serve as prognostic markers for OSCC patients.

Pt-Pd Nanoalloys Functionalized Mesoporous SnO2 Spheres: Tailored Synthesis, Sensing Mechanism, and Device Integration.

Methane (CH4 ), as the vital energy resource and industrial chemicals, is highly flammable and explosive for concentrations above the explosive limit, triggering potential risks to personal and production safety. Therefore, exploiting smart gas sensors for real-time monitoring of CH4 becomes extremely important. Herein, the Pt-Pd nanoalloy functionalized mesoporous SnO2 microspheres (Pt-Pd/SnO2 ) were synthesized, which show uniform diameter (≈500 nm), high surface area (40.9-56.5 m2 g-1 ), and large mesopore size (8.8-15.8 nm). The highly dispersed Pt-Pd nanoalloys are confined in the mesopores of SnO2 , causing the generation ofoxygen defects and increasing the carrier concentration of sensitive materials. The representative Pt1 -Pd4 /SnO2 exhibits superior CH4 sensing performance with ultrahigh response (Ra /Rg = 21.33 to 3000 ppm), fast response/recovery speed (4/9 s), as well as outstanding stability. Spectroscopic analyses imply that such an excellent CH4 sensing process involves the fast conversion of CH4 into formic acid and CO intermediates, and finally into CO2 . Density functional theory (DFT) calculations reveal that the attractive covalent bonding interaction and rapid electron transfer between the Pt-Pd nanoalloys and SnO2 support, dramatically promote the orbital hybridization of Pd4 sites and adsorbed CH4 molecules, enhancing the catalytic activation of CH4 over the sensing layer.

Regulating the Coordination Geometry and Oxidation State of Single-Atom Fe Sites for Enhanced Oxygen Reduction Electrocatalysis.

FeNC catalysts demonstrate remarkable activity and stability for the oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells and Zn-air batteries (ZABs). The local coordination of Fe single atoms in FeNC catalysts strongly impacts ORR activity. Herein, FeNC catalysts containing Fe single atoms sites with FeN3 , FeN4 , and FeN5 coordinations are synthesized by carbonization of Fe-rich polypyrrole precursors. The FeN5 sites possess a higher Fe oxidation state (+2.62) than the FeN3 (+2.23) and FeN4 (+2.47) sites, and higher ORR activity. Density functional theory calculations verify that the FeN5 coordination optimizes the adsorption and desorption of ORR intermediates, dramatically lowering the energy barrier for OH- desorption in the rate-limiting ORR step. A primary ZAB constructed using the FeNC catalyst with FeN5 sites demonstrates state-of-the-art performance (an open circuit potential of 1.629 V, power density of 159 mW cm-2 ). Results confirm an intimate structure-activity relationship between Fe coordination, Fe oxidation state, and ORR activity in FeNC catalysts.

Turbulence-resilient detection of the rotational Doppler effect with cylindrical vector beams.

Recent years have witnessed a growing research interest in the rotational Doppler effect associated with orbital angular momentum of light, emerging as a powerful tool to detect rotating bodies in remote sensing. However, this method, when exposed to the turbulence in a realistic environment, has some severe limitations, leading to the unrecognizable rotational Doppler signals overwhelmed in background noise. Here we put forward a concise yet efficient method that enables the turbulence-resilient detection of the rotational Doppler effect with cylindrical vector beams. Specifically, by adopting the polarization-encoded dual-channel detection system, the low-frequency noises caused by turbulence can be individually extracted and subtracted, and thus mitigate the effect of turbulence. We demonstrate our scheme by conducting proof-of-principle experiments, whose results manifest the feasibility of a practical sensor to detect the rotating bodies in non-laboratory conditions.

Detection of a spinning object using a superimposed optical vortex array.

The optical vortex (OV) carries unique orbital angular momentum (OAM) and experiences a Doppler frequency shift when backscattered from a spinning object. This rotational Doppler effect (RDE) has provided a solution for the non-contact detection of rotating motion. The reported RDE researches mainly use a single OV that generates frequency shifts proportional to its topological charge and has low robustness to light incidence. Here, we show the distinctive RDE of superimposed optical vortex array (SOVA). We analyze the holistic OAM of SOVA which is represented in terms of a superposition of azimuthal harmonics and displays a unique modal gathering effect. In the experiment of RDE, the frequency shift signals of SOVA show a precise mapping to the OAM modes and the modal gathering effect contributes to enhance the amplitude of signals, which has the potential to enhance robustness against non-coaxial incidence. This finding provides a new aspect of RDE and a pioneered example for introducing various SOVAs into rotation detection.