Changes In Index Research Articles

Efficient topical treatments of cutaneous lupus erythematosus: A systematic review and network meta-analysis.

Although cutaneous lupus erythematosus (CLE) has been treated with topical agents, there was no high-quality evidence of which agents were more effective, and which clinical scores were more suitable. On December 22nd, 2023, a search was conducted across five databases to identify randomized controlled trials (RCTs). Two authors independently screened the titles and abstracts of articles based on predetermined criteria. Selected articles were then assessed for inclusion in a blinded manner, with any disagreements resolved through consensus. Data were abstracted in duplicate, and a random-effects model was utilized for network meta-analysis. The certainty of the evidence was evaluated according to PRISMA guidelines, using the Grading of Recommendations Assessment, Development and Evaluation approach. The analysis was finalized in January 2024, with the primary outcome focused on the change in cutaneous lupus erythematosus disease area and severity index (CLASI) from baseline. Seven RCTs involving 231 participants were analyzed. The network meta-analysis (NMA) revealed that 4% nicotinamide demonstrated the highest probability of achieving the intended outcomes, with a mean difference (MD) of 3.10 and a 95% confidence interval (CI) of 1.99-4.21. Additionally, 0.05% clobetasol, 2% nicotinamide, and 0.1% tacrolimus also exhibited statistically significant differences, with MDs of 2.30 and 95% CIs of 0.73-3.88; 2.30 and 0.97-3.63; and 1.30 and 0.03-2.57, respectively. As data with a high level of evidence, NMAs demonstrated that 4% nicotinamide, 0.05% clobetasol, 2% nicotinamide, and 0.1% tacrolimus are statistically significant topical agents. CLASI may be an appropriate outcome to evaluate drug efficacy in CLE.

Decompression alone or with fusion for degenerative lumbar spondylolisthesis (Nordsten-DS): five year follow-up of a randomised, multicentre, non-inferiority trial

ObjectiveTo assess whether decompression alone is non-inferior to decompression with instrumented fusion five years after primary surgery in patients with degenerative lumbar spondylolisthesis.DesignFive year follow-up of a randomised, multicentre, non-inferiority...

Spillover effect of the geopolitical uncertainty on the cryptocurrency market

PurposeThis study aims to examine the influence of geopolitical uncertainty on cryptocurrency markets (CM).Design/methodology/approachUtilizing two distinct sets of daily returns data spanning from January 1, 2019, to May 4, 2023, the analysis employs the geopolitical risk (GPR) index formulated by Caldara and Iacoviello (2022), which encapsulates two pivotal events: the COVID-19 pandemic and the Russia–Ukraine conflict. The cryptocurrency market (CM) encompasses Bitcoin (BTC), Ethereum (ETH), Litecoin (LTC) and Dogecoin (DOGE). Employing the DCC-GARCH model and supplementing it with wavelet coherence analysis to discern perceptual distinctions between short- and long-term market reactions.FindingsThe main findings indicate that the GPR index clearly impacts the return of CM in the short-, mid- and long-term periods. BTC exhibited the highest volatility in response to changes in the GPR index. The cryptocurrency market offers a better diversification opportunity, and the impact of geopolitical events varies across time, with their direction and magnitude closely related to the specificity of the CM.Practical implicationsThis research is helpful for financial market investors, portfolio and risk managers, make informed decisions about including cryptocurrencies in their investment portfolios to mitigate the risks in uncertainty period.Originality/valueCryptocurrency market volatility is treated weakly during the risk period. With advanced statistical method, this study links two important events: the COVID-19 pandemic and the Russia–Ukraine conflict and selects the top four cryptocurrencies constituting 80% of the market. This study examines the impact of geopolitical risk on the cryptocurrency market and shows that this market is considered a safe haven.

Optical Detection of Underwater Propeller Wake Based on a Position-Sensitive Detector

The study of underwater vehicle wake detection is of significant importance within the field of target detection, localisation, and tracking of underwater vehicles. Given that propellers are the propellers of modern ships and underwater vehicles, the propeller wake field represents the principal target source for wake detection in underwater vehicles. The objective of this paper is to propose a method for measuring the wake of an underwater propeller based on a position-sensitive detector. A theoretical model of the relationship between the laser spot displacement and the change in the refractive index of the wake field is established on the basis of the principle of laser beam deflection. A prototype experimental setup for underwater propeller wake measurement was constructed based on the aforementioned optical measurement method. Furthermore, the simulation of the propeller wake flow field with strong density stratification and linear density stratification was conducted based on the experimental setup. Furthermore, experiments were conducted to detect the flow field of a propeller wake. The experimental results indicate that the wake dissipation times of the propeller in a strong density-stratified water environment are approximately 800 s and 750 s. Following the stabilisation of the wake field density, the laser spot position is observed to be stable at 0.341 mm and 0.441 mm, respectively, with a corresponding refractive index change of 2.99 × 10−6 RIU (refractive index unit) and 3.87 × 10−6 RIU, respectively. These experimental results are found to be in general agreement with the simulation results of the propeller wake field. A comparison of the experimental wake measurements based on the device with the wake measurements based on a CTD (conductivity–temperature–depth) device reveals a consistent trend. The realisation of this detection technique is of great significance for the advancement of research in the field of optical detection of underwater vehicle wake streams.

Effects of hydrostatic pressure, temperature, and position-dependent mass on the nonlinear optical properties of triple delta-doped GaAs quantum well

In this study, we thoroughly investigate the impacts of hydrostatic pressure, temperature, and position-dependent mass (PDM) on the nonlinear optical properties of asymmetric triple δ-doped GaAs quantum wells. Our analysis covers total optical absorption coefficients, relative refractive index changes, nonlinear optical rectification, second harmonic generation, and third harmonic generation. Initially, we employ PDM to solve the time-independent Schrödinger equation using the diagonalization method under effective mass and parabolic band approaches, considering pressure and temperature dependencies. Utilizing the first four energy eigenvalues and eigenfunctions, we apply the compact density matrix method to compute the system’s nonlinear optical properties numerically. The results indicate a shift in optical property peak positions toward lower (higher) energy spectra with increasing hydrostatic pressure (temperature). Furthermore, the influence of PDM shifts the system’s optical properties toward the higher energy spectrum, resembling the effect of temperature. From an experimental and theoretical perspective, one of the topics that researchers work on most is GaAs-based δ-doped systems (δ-doped heterojunction bipolar transistors, δ-doped field effect transistors, δ-multiple independent gate field effect transistors, etc.). We believe these findings will provide valuable insights for the researchers involved in GaAs-based δ-doped optoelectronic device design.

Human research islet cell culture outcomes at the Alberta Diabetes Institute IsletCore

ABSTRACT Human islets from deceased organ donors have made important contributions to our understanding of pancreatic endocrine function and continue to be an important resource for research studies aimed at understanding, treating, and preventing diabetes. Understanding the impacts of isolation and culture upon the yield of human islets for research is important for planning research studies and islet distribution to distant laboratories. Here, we examine islet isolation and cell culture outcomes at the Alberta Diabetes Institute (ADI) IsletCore (n = 197). Research-focused isolations typically have a lower yield of islet equivalents (IEQ), with a median of 252,876 IEQ, but a higher purity (median 85%) than clinically focused isolations before culture. The median recovery of IEQs after culture was 75%, suggesting some loss. This was associated with a shift toward smaller islet particles, indicating possible islet fragmentation, and occurred within 24 h with no further loss after longer periods of culture (up to 136 h). No overall change in stimulation index as a measure of islet function was seen with culture time. These findings were replicated in a representative cohort of clinical islet preparations from the Clinical Islet Transplant Program at the University of Alberta. Thus, loss of islets occurs within 24 h of isolation, and there is no further impact of extended culture prior to islet distribution for research.

Sustainable aviation fuel: Impact of alkene concentration on jet fuel thermal oxidative test (JFTOT)

AbstractOf the processes that are approved to produce synthetic kerosene for use in jet fuel, about half produce olefinic kerosene that is hydrotreated. The alkene concentration in synthetic kerosene is indirectly regulated through the thermal oxidative stability specification. Perceptions about the deleterious influence of alkenes on thermal oxidative stability suggest that olefinic kerosene must be deeply hydrogenated. The extent of olefin saturation required has economic implications. To evaluate what an acceptable alkene concentration in synthetic kerosene is, the impact of alkene concentration on the outcome of the jet fuel thermal oxidative stability test (JFTOT) performed at 325°C in accordance with the ASTM D3241 standard test method was experimentally evaluated. Model synthetic kerosene mixtures to which different concentrations of alkenes (1‐decene, α‐methylstyrene, indene) were added, as well as control samples were studied. In the concentration range investigated, up to 10 wt% 1‐decene, 5 wt% α‐methylstyrene, and 2 wt% indene did not lead to increased fouling in the JFTOT. Fouling passed through a minimum value with increasing alkene concentration and alkene concentration on its own was a poor predictor of thermal oxidative stability. Analysis of the kerosene collected after passing through the JFTOT found measurable changes in density and refractive index. Dissolved oxygen reacting during thermal oxidative stability testing was accounted for mostly in oxygen‐containing products in the kerosene boiling range, which indicated that the heavier products were mainly hydrocarbon in nature. In addition to initiation by autoxidation, the investigation also pointed to the existence of a second thermally initiated fouling pathway that does not require the presence of oxygen.

Electroencephalogram-Based Anesthesia Indices Differently React to Modulations of Alpha-Oscillatory Activity.

The electroencephalographic (EEG) provides the anesthesiologist with information regarding the level of anesthesia. Processed EEG indices are available that reflect the level of anesthesia as a single number. Strong oscillatory EEG activity in the alpha-band may be associated with an adequate level of anesthesia and a lower incidence of cognitive sequelae. So far, we do not know how the processed indices would react to changes in the alpha-band activity. Hence, we modulated the alpha-oscillatory activity of intraoperative EEG to assess possible index changes. We performed our analyses based on data from 2 studies. Intraoperative EEG was extracted, and we isolated the alpha-band activity by band-pass filtering (8-12 Hz). We added or subtracted this activity to the original EEG in different steps with different amplifications of the alpha signal. We then replayed these signals to the bispectral index (BIS), the Entropy Module (state entropy [SE]), the CONOX (qCON), and the SEDLine (patient state index [PSI]); and evaluated the alpha-band modulation's impact on the respective index. The indices behaved differently to the modulation. In general, indices decreased with stronger alpha-band activity, but the rate of change was different with SE showing the strongest change (9% per step) and PSI and BIS (<5% per step) showing the weakest change. A simple regression analysis revealed a decrease of 0.02 to 0.09 index points with increasing alpha amplification. While the alpha-band in the intraoperative EEG seems to carry information regarding the quality of anesthesia, changes in the alpha-band activity do neither strongly nor uniformly influence processed EEG indices. Hence, to assess alpha-oscillatory activity's strength, the user needs to focus on the raw EEG or its spectral representation also displayed on the monitoring systems.

Graphene-Based Metamaterial: Achieving Perfect Absorption Across Multiple Spectral Bands with High Sensitivity

In this paper, propose a highly sensitive absorber that utilizes graphene-based patterns to achieve perfect absorption on three different spectral bands. This absorber is designed as a traditional metamaterial structure, optimized to achieve perfect absorption. With the participation of surface plasmon resonance, the absorber achieved absorption rates of 99.14%, 98.21%, and 99.32% at resonance wavelengths of 2933.53nm, 2956.05nm, and 3360.45nm, respectively. Considering factors such as impedance matching and electric field, provide a comprehensive physical explanation for the generation of these absorption peaks. In addition, demonstrated how can modify the wavelength of the absorption peak by adjusting the Fermi energy, and fine tune the absorption rate of a fixed wavelength by manipulating the relaxation time, thereby demonstrating the versatility of our design. In addition, this research explored the complex relationship between the Fermi level and the resonant wavelength and studied the influence of the refractive index of the dielectric layer on the resonant wavelength. It is worth noting that this relationship can be expressed as a strict linear function. As the external refractive index changes, calculated the sensitivity of the absorber, with a peak sensitivity of 768.75nm/RIU (refractive index unit). This high sensitivity corresponds to a quality factor of 93.31 for the absorption peak. At the same time, our absorber also has good insensitivity to incident angles. In summary, due to its outstanding performance characteristics, this research proposed absorber has broad application prospects in fields such as optoelectronic detection and high sensitivity sensors.

Optical absorption properties in multi-layer InGaN/GaN core-shell quantum dots: The influences of ternary mixed crystal effect and hydrogen-like impurity

Based on the effective mass approximation and the compact density matrix theory, the electronic states and optical absorption properties of intersubband transitions between the conduction-band energy levels in zinc-blende InGaN/GaN/InGaN/GaN core-shell quantum dots (CSQDs) are investigated by using the finite difference method. The effects of hydrogen-like impurity and In component on the wave functions, transition energies, and optical absorption properties are discussed in detail. The results show that hydrogen-like impurity can cause the peak positions of optical absorption coefficients (OACs) and refractive index changes (RICs) to move to high energy area, and the peak values of OACs rise. Increasing In component of InGaN crystal in the core region of a CSQD has the same effect. But an opposite tendency will be found when increasing In component in the shell-well of a CSQD, i.e. optical absorption peaks move to low energy area and their values decrease. Comparing to the shell-well, the core region has more powerful confinement effect on electrons. So the better absorption properties are more likely to be obtained for this type of multi-layer InGaN/GaN CSQDs when In component in the core is larger than that in the shell-well.

Evaluation of acute and midterm outcomes after complex combined antegrade/retrograde recanalization for occlusions of the femoropopliteal and infrapopliteal arteries

IntroductionWhen antegrade recanalization of femoro- and/or infrapopliteal occlusions fails, retrograde access has become an established option. To evaluate the results of combined antegrade and retrograde recanalization of femoropopliteal and infrapopliteal occlusions, patients undergoing secondary retrograde recanalization attempts were analyzed retrospectively. MethodsPrimary endpoint was the success of the procedure (successful occlusion crossing using the ante-/retrograde technique). Secondary endpoints include complication rate, primary patency and target lesion revascularization (TLR) rate, amputation rate, changes in ankle-brachial index (ABI), and Rutherford-Becker class (RBC). Predictors for procedure failure and TLR were analyzed. ResultsWe included 888 patients: 362 with femoropopliteal (group 1), 353 with infrapopliteal (group 2), and 173 with multi-level (group 3) recanalization. Critical limb threatening ischemia (CLTI) was present in group 1, 2, and 3 in 36%, 62%, and 76%, respectively. The intervention was successful in 92.5%, 93.8%, 90.8% of respective cases (p=0.455). The overall peri-interventional complication rate was 7.2%.At 6, 12 and 24 months, primary patency was highest in group 1 (63.9%, 45.8%, 33.3%), followed by group 3 (59.8%, 46.1%, 33.3%), and group 2 (58.5%, 43.1%, 30.4%), p=0.537).The risk of undergoing repeated TLR within 24 months was 31.4% for group 1, 39.1% for group 2, and 45.7% for group 3.At 24 months, the survival rate in groups 1, 2, 3 was 93.8%, 79.4% and 87.5%, respectively. During 24 months, 75 patients (8.4%) had to undergo amputation. Significant improvements in both ABI and RBC were present at discharge as well as at 6, 12 and 24 months (p<0.001).Dialysis dependency was a predictor of unsuccessful ante/retrograde recanalization (p=0.048).Lesion length (p=0.0043), dialysis (p=0.033) and recanalization level (p=0.013) increase the risk of TLR. ConclusionUsing a combined antegrade/retrograde access, recanalization of occluded femoropopliteal and/or infrapopliteal arteries can be achieved in a large number of cases. Due to the high rate of repeated TLR across all lesion localizations, the indication for ante- and retrograde recanalization may be limited to patients with CLTI.

Childhood sexual abuse and IL6 mediated by change in BMI over an 18-year period: A growth curve model

BackgroundChildhood sexual abuse can increase both body weight and inflammation later in life. Higher weight or faster changes in weight, as measured by changes in body mass index (BMI), may mediate the relationship between childhood sexual abuse and inflammation, however, most studies to date have used a cross-sectional design limiting causal inferences. ObjectiveThe current study aimed to investigate the interrelationships between childhood sexual abuse, BMI, and C-reactive protein (CRP) and interleukin-6 (IL6).Participants and Setting.Data from 461 adults who participated in the Midlife in the United States (MIDUS) study were utilized. MethodsGrowth curve modeling was used to test initial levels of BMI and changes of BMI over an 18-year period as mediators linking childhood sexual abuse to CRP and IL6. ResultsSexual abuse was not significantly associated with the initial level of BMI; however, sexual abuse was associated with the slope of BMI (b = 0.072, p = .006). BMI intercept (b = 0.080, p = .001) and slope (b = 0.240, p = .002) predicted IL6 values whereas the slope of BMI (b = 0.398, p = .033) but not intercept predicted CRP values. The indirect effect from sexual abuse to IL6 through BMI slope was significant (b = 0.017, 95 % [CI.001, 0.033]) while the indirect effect from sexual abuse to CRP through BMI slope was not significant (b = 0.028, 95 % [CI -0.004, 0.061]). ConclusionChildhood sexual abuse was indirectly associated with IL6 through rates of change in BMI over time.

Changes in callosal angle and Evans index after shunt surgery in patients with idiopathic normal pressure hydrocephalus

BackgroundIdiopathic normal pressure hydrocephalus (iNPH) is a disease characterized by gait disturbance, cognitive impairment and urinary incontinence. For those patients who do not respond to shunt surgery, it lacks objective radiological findings for the diagnosis of shunt malfunction. Here we aimed to evaluate whether Evans index and callosal angle change during a prospective long-term follow-up of patients with iNPH submitted to shunt surgery. MethodsClinical (NPH Japanese Scale) and radiological (Evans index, callosal angle) data were collected pre- and postoperatively (3, 6, 12 months) in 19 patients with iNPH. Imaging tests were evaluated by the same neuroradiologist during the follow-up. ResultsPatients had lower scores on NPH Japanese Scale over time (p< 0.001). There was no significant difference among Evans index values during the follow-up (p= 0.24). Preoperative average callosal angle was 72 ± 15, which increased to 91 ± 18 in 6 months (p= 0.003). ConclusionsIn this sample, patients with iNPH submitted to a programmable valve shunt had an increase in callosal angle concomitant to neurological improvement. Evans index did not change during follow-up.

Tunability of Sb2Se3 phase change material for multi-domain optoelectronics

Phase change materials play an essential role in the development of tuneable optics by overcoming the limitations possessed by conventional optics due to their static behaviour. Due to their non-volatile nature, chalcogenide materials attained attention beyond other phase change materials. Antimony-based chalcogenides are promising due to low absorption loss, optimal refractive index change, and compatibility with silicon integration. This study optimises near-stoichiometric sputtered Sb2Se3 thin films and investigates their compositional, physical, and optical properties change by thermal, optical, and electrical stimuli. We further extend the investigation to the induced intermediate states in the Sb2Se3 thin film for multi-bit operation for tunable photonics and phase-change memory with a current switching ratio of 104 during a phase transition. The findings are integral to the realisation of high-capacity optical switches and routers, displays with larger colour distribution, and photonic memories with high computational capabilities.

Comparative Study of Heat Transfer and Flow Friction in Plate Heat Exchangers with CarboxyMethyl Cellulose and Sodium Alginate

Abstract: Study of Plate heat exchanger (PHE) with power law fluid is a very interesting topic now a days as there is improvement of thermal performance of heat exchanger. Power law fluids show complex flow behavior due to its rheological properties. The parameters which differ these power law fluids from Newtonian fluids are rheological properties like flow behavior index and power law index. Hence flow behavior index and power law index are the two parameters which affect the heat transfer rate. Now to enhance rate of heat transfer we should know how Nusselt number changes with change in flow behavior index and power law index. Hence the aim of present study was to observe how Nusselt number and friction factor changes with change in flow behavior index and power law index. For this purpose thermal performance of PHE have been studied with CorboxyMethyl Cellulose (CMC) and sodium alginate as a cold fluids. Comparison of Nusselt number and friction factor of CMC and sodium alginate have been done. It was observed that Nusselt number for CMC solution was more compared to sodium alginate solution with less friction factor than sodium alginate.

Comparative Study of Heat Transfer and Flow Friction in Plate Heat Exchangers with CarboxyMethyl Cellulose and Sodium Alginate

Abstract: Study of Plate heat exchanger (PHE) with power law fluid is a very interesting topic now a days as there is improvement of thermal performance of heat exchanger. Power law fluids show complex flow behavior due to its rheological properties. The parameters which differ these power law fluids from Newtonian fluids are rheological properties like flow behavior index and power law index. Hence flow behavior index and power law index are the two parameters which affect the heat transfer rate. Now to enhance rate of heat transfer we should know how Nusselt number changes with change in flow behavior index and power law index. Hence the aim of present study was to observe how Nusselt number and friction factor changes with change in flow behavior index and power law index. For this purpose thermal performance of PHE have been studied with CorboxyMethyl Cellulose (CMC) and sodium alginate as a cold fluids. Comparison of Nusselt number and friction factor of CMC and sodium alginate have been done. It was observed that Nusselt number for CMC solution was more compared to sodium alginate solution with less friction factor than sodium alginate.

Phrenic nerve stimulation for central sleep apnea: a single institution experience.

Phrenic nerve stimulation (PNS) was approved by the Food and Drug Administration (FDA) to treat moderate to severe central sleep apnea. We report here, results of a retrospective study regarding our institutional outcomes at one year. In this study we evaluated the change in the apnea hypopnea index, epworth sleepiness score, and functional outcomes of sleep score at one year post implant. This is a retrospective analysis of patients ≥ 18 years of age who had PNS implanted for moderate to severe CSA at the Ohio State University Wexner Medical Center apnea between Feb 1, 2018 to July 1, 2021. Sleep disordered breathing parameters and objective sleepiness as measured by the Epworth Sleepiness Scale (ESS) scores, and Functional Outcomes of Sleep Questionnaire (FOSQ) scores were assessed at baseline and one-year post-implant. Twenty-two patients were implanted with PNS at OSU between February 1, 2018 and May, 31, 2022. The AHI showed a statistically significant decrease from a median of 40 events/hour at baseline to 18 at follow-up (p-value = 0.003). The CAI decreased from 16 events/hour to 2 events/hour (p-value of 0.001). The obstructive apnea index, mixed apnea index, and hypopnea index did not significantly change. The ESS scores had a statistically significant improvement from a median score of 12 to 9 (p-value = 0.028). While the FOSQ showed a trend to improvement from 15.0 to 17.8, it was not statistically significant (p-value of 0.086). Our study found that PNS therapy for moderate to severe CSA improves overall AHI and CAI. Objective sleepiness as measured by the ESS also improved at one-year post implant.

Multi-modal flexible and inexpensive plasmonic metasurface for wide range of refractive index sensing

Abstract A plasmonic metasurface containing nanobumps of sub-wavelength feature size arranged in a hexagonal pattern on a flexible substrate and covered with a thin film of gold is investigated as a refractive index sensor. The chosen polymer patterns coated with gold aid in activating the surface plasmon polariton modes. Using numerical calculations, it is shown that this surface can exhibit plasmonic effect with an extremely shallow pattern height of 92.5 nm and minimal thickness of 25 nm of gold over it. The excitation of the plasmonic modes is confirmed using electric field profiles calculated at the relevant wavelengths. As the surface is highly sensitive to changes in the cladding index, and the chosen design aids in exciting three plasmon modes that are suitably well-separated in wavelength, this surface can be used for an extremely wide range of refractive index sensing because each mode contributes uniquely to a different range of refractive index. The results establish that the metasurface is suitable for a variety of applications, including gas detection with a sensitivity of 633 nm/RIU using mode-1, identifying SARS-CoV-2 viral molecules with a sensitivity of 428 nm/RIU using mode-2 and 238 nm/RIU using mode-3, and discriminating between normal and diseased brain tissues in the cerebrospinal fluid in the high-index range using mode-3. The prototype metasurface is made using a cost-effective soft lithography technique using an economical master mould. The inexpensive technique of fabrication, use of very thin metal film, and wavelength of detection lying within the visible to near infrared range imply a low-cost sensor. The structural and optical characterization of the prototype validates the numerical study of the sample.

The effect of the external magnetic field on the power of the laser passing through the magnetized plasma and the calculation of the radius of convergence and the investigation of the condition of the beam's filamentation in the Medium

In this article, the power of a laser passing through a magnetized plasma medium which is affected by an external magnetic field is calculated.The change in the intensity of the magnetic field and its rotation around the axis of laser beam propagation in the plasma, on the power of the passing beam is investigated.This work is done based on the indirect effect of the magnetic field on the density distribution of electrons in the plasma, which we can consider the density changes as changes in the refractive index of the medium, so the laser power in this case is different from the case where there is no magnetic field. Also, the condition of beam filamentation has been researched as one of the third-order nonlinear phenomena, and the convergence radius has been calculated under these conditions.

Multi-Fano resonances by TCS and resonance-enhanced TES in hybrid photonic crystals for ultracompact sensing

This work introduces a novel hybrid photonic crystal (PC) architecture exploiting topologically multi-Fano resonances employing an inverted π-shape structure filled with a nontrivial PC flanked by M−shaped trivial PCs for ultracompact and high-sensitivity sensing, harnessing their immense potential for miniaturized sensing applications. Topological corner state (TCS) is formed in the structure. Moreover, a waveguide-branch resonator or a resonant ring for the topological edge state (TES) mode is formed to increase the Fano resonance. We demonstrate the existence of engineered quasi-bound multi-Fano resonances within this structure, exhibiting tunable quality factors exceeding 108 (ultrahigh Q) and a remarkable figure of merit (FOM), reaching 2.6×107RIU-1. By precisely controlling the nontrivial PC dimensions, we achieve exquisite control over the resonance’s Q factor and spectral line shape, revealing characteristics of quasi-bound states in the continuum (BICs). This hybrid architecture exhibits exceptional sensitivity to refractive index changes, with tunability ranging from 320 to 392 nm/RIU. Our work paves the way for a new paradigm in sensing, enabling the development of ultracompact on-chip nanophotonic devices with unprecedented sensitivity and control.