Double Resonance Peaks Research Articles

Nonlinear vibrations of variable speed rotating graphene platelets reinforced blades subjected to combined parametric and forced excitation

It is generally acknowledged that the disturbance of rotating speed will cause parametric resonance for blades, and the presence of rotor displacement also can make the blade vibrate transversely. However, the coupled resonance mechanism of blades under the combined action of rotating speed disturbance and rotor displacement is not yet clear. To answer this question, this article investigates the nonlinear coupled resonance behavior of rotating blades in two cases: typical tuned (the frequency ratio of parametric and forced excitations equals 2:1) and frequency ratio detuned. A nonlinear vibration equation for rotating blades is established based on Euler beam theory in conjunction with geometric nonlinearity. The mixing rule and modified Halpin-Tsai model are used to calculate the effective properties of GPLRMF materials. Subsequently, using the method of varying amplitudes (MVA), an approximate analytical solution of the coupled resonance response is derived, the Jacobian matrix is used to determine the stability of non-trivial solutions, and the accuracy of the analytical results is verified with the aid of numerical solutions. Finally, the steady-state response of typical tuned and detuned coupled resonance is analyzed, and the influence mechanism of factors such as excitation amplitude, excitation phase angle and other parameters on coupled resonance is studied in detail. The results indicate that the supercritical coupled resonance curve exhibits double resonance peaks and jumps. Meanwhile, the steady-state response of coupled resonance highly depends on the excitation phase angle.

Qualitative and Quantitative Detection of Typical Reproductive Hormones in Dairy Cows Based on Terahertz Spectroscopy and Metamaterial Technology.

Progesterone (PROG) and estrone (E1) are typical reproductive hormones in dairy cows. Assessing the levels of these hormones in vivo can aid in estrus identification. In the present work, the feasibility of the qualitative and quantitative detection of PROG and E1 using terahertz time-domain spectroscopy (THz-TDS) and metamaterial technology was preliminarily investigated. First, the time domain spectra, frequency domain spectra, and absorption coefficients of PROG and E1 samples were collected and analyzed. A vibration analysis was conducted using density functional theory (DFT). Subsequently, a double-ring (DR) metamaterial structure was designed and simulated using the frequency domain solution algorithm in CST Studio Suite (CST) software. This aimed to ensure that the double resonance peaks of DR were similar to the absorption peaks of PROG and E1. Finally, the response of DR to different concentrations of PROG/E1 was analyzed and quantitatively modeled. The results show that a qualitative analysis can be conducted by comparing the corresponding DR resonance peak changes in PROG and E1 samples at various concentrations. The best R2 for the PROG quantitative model was 0.9872, while for E1, it was 0.9828. This indicates that terahertz spectral-metamaterial technology for the qualitative and quantitative detection of the typical reproductive hormones PROG and E1 in dairy cows is feasible and worthy of in-depth exploration. This study provides a reference for the identification of dairy cow estrus.

Simultaneous Detection of Temperature, Strain, Refractive Index, and pH Based on a Phase-Shifted Long-Period Fiber Grating

A novel π-phase-shifted (PS) long-period fiber-grating (LPFG) sensor operating near the phase-matching turning point (PMTP) was proposed. The PS-LPFG sensor can simultaneously detect temperature, strain, refractive index (RI), and pH. Due to the introduction of π phase shift, the double resonance peak of the selected cladding mode was divided into four loss peaks, which is convenient for multiparameter measurement. By monitoring the resonant-wavelength shifts of four dips of PS-LPFG, simultaneous detection of temperature, strain, RI, and pH can be achieved. Moreover, using a simple LPFG design on one fiber and a multiparameter matrix algorithm, the crosstalk between multiple signals was eliminated. Graphene oxide/polyvinyl alcohol (GO/PVA) hydrogel was coated onto the grating sensing area to measure the change in pH, and the sensitivity was higher than that of the same type of fiber-grating sensor. Results showed that the maximum sensitivity of temperature, strain, RI, and pH of the fabricated phase-shifted grating sensing structure were 0.2128 nm/°C, 0.1225 nm/μϵ, 718 nm/RIU, and -1.0166 nm/pH, respectively. Overall, the proposed sensor had great potential applications in monitoring marine environments and biochemistry sensing.

Anomalous and inverse spin Hall effects in Pt1-xBix/(YLuBiCa)3(FeGa)5O12 heterojunction

A garnet film with spatial magnetic moment distribution has been grown on gadolinium gallium garnet wafer (111) crystal plane, by regulating liquid phase epitaxial growth parameters and sub-lattice ions substitution, then 10 nm Pt1-xBix (x = 2% – 8%) alloy film was deposited on the surface of the garnet films. A new spin heterojunction Pt1-xBix/(YLuBiCa)3(FeGa)5O12 with both inverse spin Hall effect (ISHE) and anomalous spin Hall effect (ASHE) was designed and fabricated. The spatial magnetic moment distribution of the heterojunction has been found, which lays the foundation of the spin heterojunction for multiple spin injection with both spin electron reverse injection and anomalous injection. Because Bi ions doping and substitution increases the spin–orbit torque and the mixed conductance of the heterojunction, an oblique ASHE voltage curve and an enhanced ISHE voltage curve with double resonance peak were observed. It was confirmed that the injection of spinning electron into the heterojunction can be enhanced with both the ISHE and ASHE effect by adjusting the spatial magnetic moment distribution, which is a foundation for the future application of spin wave 3D antenna and other devices.

Double resonance peak phenomenon and balance method of rotating machinery with flexible bearing support

A simplified dynamic model of the rotor-bearing-support system is established considering the influence of pedestal flexibility. The vibration characteristics of the system with a flexible pedestal are analyzed. There are two resonance peaks during the run-up process for this kind of system. It is generally thought that the stiffness difference in the vertical and the horizontal direction is the main cause of the double resonance peak phenomenon. The results of the paper show that the flexible pedestal support also causes the double resonance peak phenomenon. The shaft relative vibration cannot reflect the influence of rotor unbalances well near the resonance zone. In this case, the bearing vibration should be preferred in the balance test. The vibration phenomenon on an actual unit is analyzed as an example.

An active damping control strategy with improved transient performance for high‐frequency AC power distribution in intelligent vehicles

SummaryHigh‐frequency AC (HFAC) LCLC resonant inverter has recently received more and more attention in power distribution system (PDS) of intelligent vehicles. However, LCLC resonance complicates the design of a current control loop and can even threaten the stability and transient performance of PDS. Active damping (AD) strategies based on the feedback of a single filter voltage or current have been shown to be effective and cost‐efficient method for attenuating resonant spikes. In this paper, a notch filter‐based AD (NFAD) control strategy is proposed to improve the stability and transient performance of PDS for intelligent vehicles. By sensing and feeding back the output resonance current of LCLC resonant inverter, the NFAD control strategy is then formulated to emulate a virtual impedance in order to improve the system phase margin and crossover frequency. Hence, the proposed control strategy can not only suppress the LCLC double resonance peaks but also effectively improve the transient performance of resonant inverter while guaranteeing the stability of the system. Finally, an experimental prototype was established and tested to verify the effectiveness of the proposed control strategy with a rated output power of 130 W, an operation frequency of 25 kHz, and a sinusoidal output voltage of 28 V (rms).

Research on Tunable SPR Sensors Based on WS2 and Graphene Hybrid Nanosheets

A prismatic excitation-based affinity biosensor consisting of the prism (BK7), WS2/graphene hybrid nanosheets, and silver (Ag) as the active metal for the surface plasmon resonance is proposed in this present research. The introduction of the transition metal WS2/graphene layer protected the silver substrate and enhanced the adsorption of biomolecules, which facilitated the quality and performance of detection. Here, we improved the detection structure by focusing on the metallic materials, graphene and WS2 film layers, and the thickness of the measured medium on the sensing effect. The results show that the silver film had a more desirable resonance effect, and the design of the symmetric detection structure produced a double resonance peak, and it provides a reference for distributed sensing. Changing the thickness of the detection medium can dynamically adjust the wave vector matching conditions, which gives the sensor a certain tunability. In the bilayer WS2 and monolayer graphene (W = 2, G = 1) configuration, the sensitivity was up to 224 deg/RIU with a quality factor of 96.97 RIU−1, which has potential for clinical analytic and biochemical detecting applications.

Resonance behavior of fractional harmonic oscillator driven by exponentially correlated dichotomous noises

This paper investigates the resonance behaviors of a fractional-order harmonic oscillator driven by two exponentially correlated dichotomous noises, where the Caputo fractional derivative operator is applied to describe the power-law memory of the system. By using the stochastic averaging method and the Shapiro-Loginov formula, we derive the analytical expression of the output amplitude gain of the system, from which the existence and the correlation of noises are found to be keys for the occurrence of resonance. When either of the noises is absent or they are uncorrelated, the output amplitude gain is zero, indicating that the system is dissipative in this case. The numerical simulation shows that the system has rich resonance behaviors when noises are exponentially correlated. Three types of resonance, that is, the bona fide resonance, the classic stochastic resonance and the generalized stochastic resonance, are observed. And the effects of system parameters on these resonance behaviors are well discussed. Specifically, double-peak resonance and damping-coefficient–induced resonance are observed only in the fractional-order system rather than integer-order system.

Design of an ultra-broadband optical filter based on a local micro-structured long period fiber grating near PMTP.

This paper presents a local micro-structured long period fiber grating (LMS-LPFG) ultra-broadband optical filter based on the wide bandwidth near the phase-matching turning point (PMTP). The structure of LMS-LPFG is obtained by dividing a LPFG into two parts of equal length and reducing the cladding radius of the second LPFG. At this time, the LMS-LPFG can be regarded as a cascade of two equal-length LPFGs with different resonance wavelengths. The cladding mode and grating period are determined to make the first LPFG work in the double-peak resonance state, and the second LPFG operates near PMTP. It is found that the transmission spectra of the two LPFGs can be superimposed to form a wide loss bandwidth. Then the cladding radii of the second LPFG and grating structure parameters are designed based on coupled-mode theory. First, the grating period corresponding to the operating wavelength is determined from the phase-matching curve of LMS-LPFG. Then, the radius of the second LPFG with a designated grating period is selected to make LPFG 2 work in PMTP by reducing its cladding radius. In addition, the grating lengths of the two LPFGs are determined by maximizing the loss of the LMS-LPFG's transmission spectrum. Finally, the two LPFGs are cascaded into a LMS-LPFG, and the optical transmission spectrum of the LMS-LPFG is calculated by the transfer matrix method. Simulation results show that the bandwidth of the transmission spectrum can reach 380 nm. In addition, the flexibility of design for the operating wave band is discussed and confirmed, and can meet different actual requirements of optical communication.

LSPR Based Double Peak Double Plasmonic Layered Bent Core PCF-SPR Sensor for Ultra-Broadband Dual Peak Sensing

Through this paper, a sensor based on localized surface plasmon resonance (LSPR) with simultaneous use of gold and aluminium doped zinc oxide (AZO) as plasmonic materials has been proffered. Incorporating these two different plasmonic materials has brought out a unique dispersion relation where double resonance peaks have been detected. After optimizing structural parameters, the simulated results have distinguished that this sensor exhibits maximum amplitude sensitivity of 8485.2 RIU <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> along with maximum wavelength sensitivity of 46300 nm/RIU in the direction of y-polarization whenever AZO is used as the middle plasmonic material. Furthermore, the sensor obtains a maximum amplitude resolution of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.18\times 10$ </tex-math></inline-formula> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−6</sup> RIU and a maximum wavelength resolution of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.16\times 10$ </tex-math></inline-formula> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−6</sup> RIU. A higher figure of merit of 2923.2 can also be obtained, indicating higher detection accuracy through this sensor and maximum linearity of R <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> = 0.99312. Moreover, the proffered sensor has shown its ability to detect unspecified analytes with a refracting index in the maximum wide range of 1.27 to 1.45. Apart from these sensing parameters obtained from analyzing the double peaks separately, a new sensing parameter called double peak shift sensitivity has been introduced in this study. This sensor displays a maximum double peak sensitivity of 4400 nm/RIU for x-polarization mode and 16500 nm/RIU for y-polarization mode considering the double peaks together for two adjacent RIs. Due to these diverse features, the proposed design can open the doors to notable developments in a wide range of analytes and biological organic chemicals detection with ultra-high accuracy and broadband applications.

Distinct local angular chiroptical effects with unidirectional emission based on asymmetric plasmonic nanopillar antennas

Here, we observed the local angular chiroptical effects with unidirectional emission based on exquisitely designed plasmonic nanopillar antennas. Firstly, the scattering spectra for the asymmetric nanoantennas show double resonant peaks when illuminated by circular polarized light. The calculated circular dichroism reaches the maximum value at one resonant peak while almost disappears at the other peak. Secondly, when we turn to the momentum space for the CD-disappeared peak, the asymmetric nanoantennas exhibit different angular emission patterns that are sensitive to the handedness of light, which indicate the existence of the local angular chiroptical effects. The emission patterns also show unidirectional emission lobes in momentum space, which is distinct to other chiral phenomenon. Multipolar expansion and Green’s function method in stratified medium is used to demonstrate the inner mechanism of the observed local angular chiroptical effects, and we found the phase difference of the multipolar resonance is the origin of the distinct local angular chiroptical effects. Our work investigating the local angular chiroptical effects based on nanopillar will shed new light on optical chirality and will be widely applied to wavelength router, photon-detection, and other optoelectronic devices.

Double-peak resonant mapping of cellular viscoelasticity in force-clamp detection of atomic force microscope

The mechanical properties of cells are very important to their physiological functions and pathological states, and their variations are also potential indications for early identification of the relevant diseases such as various cancers. With the development of microcantilever sensor, the atomic force microscope (AFM) has become one of the most commonly used tools to detect nanoscale biomolecular mechanical properties. In this contribution, an integral type inhomogeneous viscoelastic moving boundary effect in AFM system is accurately delineated, and a potential conceptual proposal of using the double-peak resonance for microcantilever dynamic system is suggested to detect viscoelasticity of fixed cells. Mathematical models for the quasi-static and dynamic responses of microcantilever system with a viscoelastic moving boundary effect are presented. Laplace transform and its inverse transform, and differential method in the temporal domain and extended differential quadrature method (DQM) in the spatial domain are combined to obtain the relevant analytical solutions for quasi-static response and numerical solutions for dynamical response. Analytical results for quasi-static response agree well with the previous experiments and our simulations by the extended DQM. The results not only reveal that moving boundary conditions and cellular viscoelasticity cannot be ignored for signal extractions in the processes of cellular detection due to their significant influence on interaction force, bending deflection, natural frequency, and mode shape of microcantilever system, but also indicate a double-peak resonance-based method that could be potentially used to identify the transient-, steady-state modulus, and relaxation time of fixed cells.

A neutron diffraction investigation of high valent doped barium ferrite with wideband tunable microwave absorption

The barium ferrite BaTixFe12−xO19 (x = 0.2, 0.4, 0.6, 0.8) (BFTO-x) ceramics doped by Ti4+ were synthesized by a modified sol—gel method. The crystal structure and magnetic structure of the samples were determined by neutron diffraction, and confirm that the BFTO-x ceramics were high quality single phase with sheet microstructure. With x increasing from 0.2 to 0.8, the saturation magnetization (Ms) decreases gradually but the change trend of coercivity (Hc) is complex under the synergy of the changed grain size and the magnetic crystal anisotropy field. Relying on the high valence of Ti4+, double resonance peaks are obtained in the curves of the imaginary part of magnetic conductivity (μ″) and the resonance peaks could move toward the low frequency with the increase of x, which facilitate the samples perform an excellent wideband modulation microwave absorption property. In the x = 0.2 sample, the maximum reflection loss (RL) can reach −44.9 dB at the thickness of only 1.8 mm, and the bandwidth could reach 5.28 GHz at 2 mm when RL is less than −10 dB. All the BFTO-x ceramics show excellent frequency modulation ability varying from 18 (x = 0.8) to 4 GHz (x = 0.4), which covers 81% of the investigated frequency in microwave absorption field. This work not only implements the tunable of electromagnetic parameters but also broadens the application of high-performance microwave absorption devices.

Double-peaked resonance in harmonic-free acoustically driven ferromagnetic resonance

The resonant interaction between surface acoustic waves and ferromagnetic thin films, a phenomenon known as acoustically driven ferromagnetic resonance (ADFMR), provides a way to control magnetic resonance with purely voltage excitation. However, devices have historically been operated at harmonic frequencies, leading to large insertion losses. In this work, we demonstrate a harmonic-free drive of ADFMR devices where the strain reaches very high values, comparable to the saturation magnetostriction of the magnetic element. The acoustic energy transfer is highly efficient and reaches almost 99.9%. Furthermore, we report the presence of multiple absorption maxima across the range of applied magnetic fields, a property not previously observed in the literature.

Tunable Fano resonance in plasmonic MIM waveguide with P-shaped resonator for refractive index sensing

Based on the transmission characteristic of surface plasmon polaritons (SPPs), a compact plasmonic system based on a sub-wavelength metal-insulator-metal (MIM) waveguide coupled with P-shaped cavity is proposed. The results show that double Fano resonance peaks are generated in the transmission spectra, which has been studied by the finite-element method (FEM). The transmission spectrum of the system is theoretically verified by the multimode interference coupled mode theory (MICMT) perfectly. In addition, the simulation results show that the position of the resonance peaks can be adjusted by changing the structural parameters. The sensing characteristics of the resonant cavity are also studied, and the refractive index sensitivity and the figure of merit (FOM) are 2100 nm /RIU and 189.97. The results effectively improve the sensitivity and FOM of nano-scale plasmonic sensors and provide significant guidance for the application of tunable multiple Fano resonance in refractive index sensors, biosensors, optical switches and other plasmonic devices.

Stochastic resonance induced weak signal enhancement over controllable potential-well asymmetry

A dynamical model submerged in two colored multiplicative and additive noises by colored cross-correlation is established to elaborate controllable asymmetric potential-well with depth-asymmetry and width-asymmetry. We deduce the approximate signal-to-noise ratio (SNR) as widely adopted indicator for quantifying stochastic resonance (SR) behavior in accordance with the two-state theory, where the largest SNR peaks are almost attained in the asymmetry case. Moreover, the non-monotonic resonance curves excited by the incremental multiplicative colored noise intensity show the typical SR phenomenon and the SNR peaks decline as the additive colored noise intensity increases, the SR behavior induced by multiplicative colored noise is different from that induced by varying additive one. Noteworthy, the self-correlation time of alternative noises are more effective for controlling SR than cross-correlation time of noises. More interestingly, the output SNR demonstrates double resonance peaks by varying the cross-correlation intensity from negative to positive, however, the two local optimal cross-correlation intensities are almost maintained constant as the increasing of additive noise intensity. Even the large asymmetric well-depth is always beneficial to the improvement of SNR in comparison with well-width asymmetry at the same situation, which is due to the much more energy harvesting from the noises.

Enhanced and tunable double Fano resonances in plasmonic metasurfaces with nanoring dimers

The appearance of the double-resonance substrate has promoted the application of surface-enhanced Raman scattering (SERS). By controlling the frequencies of the double resonances to match the excitation and Raman scattering frequencies, the detection of the object to be measured can be more effective. For the double-resonance substrate, while the resonance frequencies can be highly controllable, the electric field enhancement is also one of the important factors affecting the application in SERS. In this paper, we designed a metasurface composed of a nanoring dimer array, silica dielectric and gold film. The nanoring dimer array and gold film are separated by the silica dielectric to form a resonant cavity. The localized surface plasmon resonance generated in the nanoring dimer array is coupled with the cavity mode of the resonant cavity. Double Fano resonance with strong electric field enhancement is generated at the gap of the nanoring dimer. The electric field enhancement value can reach 100, which is an order of magnitude larger than that of the nanoring metasurface without the gap structure. The double Fano resonance peaks can be flexibly adjusted while maintaining large electric field enhancements by changing the following parameters: the period of the nanoring dimer array along the direction of the short axis, the ratio of the inner and outer radius of the nanoring and the length of the resonant cavity. Therefore, the proposed metasurface-enhanced Raman scattering substrate provides both the enhanced and tunable double Fano resonances necessary for high-sensitivity, high-selectivity and high-throughput detection. In addition, we proved that the length of the cavity can be determined by theoretical calculation, which avoids a lot of simulation processes.

Double stochastic resonance induced by varying potential-well depth and width

The role of potential-well depth and width on stochastic resonance (SR) driven by colored noise with different noise correlation times is explored and evaluated by deriving the analytic expression of output signal-to-noise ratio (SNR) as a most widely used indicator for quantifying SR phenomenon. Double resonance peaks are observed and shifted between single peak and double peaks when SNR is expressed as the function of varying potential-well depth, varying potential-well width, additive noise intensity, multiplicative noise intensity and the intensity ratio between two noise, respectively. Moreover, the SR behavior induced by varying potential-well depth is different from that induced by varying potential-well width. Even the shapes of SNR curves under different correlation times and coupling strength for potential-well depth are opposite to those for potential-well width and furthermore they are also of dependence on initial conditions. Above clues may be helpful to the precise control of SR by varying potential-well depth and width separately for weak signal enhancement.

Sensing characteristics of dual band terahertz metamaterial absorber sensor

&lt;sec&gt;The terahertz metamaterial absorber sensor is an important functional device of the metamaterials. It can realize not only the perfect absorption in the incident terahertz wave, but also the detect sample by monitoring the deviation of the absorption frequency of the metamaterial absorber sensor. &lt;/sec&gt;&lt;sec&gt;Dual-band metamaterial absorber sensor has double frequency resonance peak. By matching the characteristic frequency between the sensor and the substance to be measured, the information reflecting the difference of the substance to be measured is increased, to improve the accuracy and sensitivity of material detection. Compared with the traditional metamaterial absorber sensor, the dual-band metamaterial absorber sensor can realize very accurate sensing and detection function through multi-point matching of information. &lt;/sec&gt;&lt;sec&gt;In this paper, a double band terahertz band metamaterial absorber sensor is proposed. The absorption rate of the metamaterial absorber sensor reaches over 99% at 0.387 THz and 0.694 THz frequency point, achieving “perfect absorption”. Through the analysis of a series of materials with different refractive indices to be measured, the suitable sensing range of the designed terahertz metamaterial absorber sensor is obtained. By analyzing the different thickness of the substance to be measured and the different medium layer materials, the thickness of the substance to be measured and the medium layer materials which can improve the sensing performance of the sensor are obtained. In this paper, the sensing identification of edible oil is taken for example to verify that the dual-band terahertz metamaterial absorber sensor designed in this paper can realize high sensitivity and rapid detection, and has a broad development prospect in the field of sensing and detection.&lt;/sec&gt;

Au@SiO2@Au core-shell-shell nanoparticles for enhancing photocatalytic activity of hematite

Photoelectrochemical (PEC) water splitting for hydrogen generation using abundantly available solar energy is a promising strategy toward developing a carbon-neutral society. Here, we demonstrate the first use of Au@SiO2@Au core-shell-shell (CSS) plasmonic nanoparticles (NPs) for improvement of the photocatalytic performance in PEC photoanodes using hematite as a testing system. Using rigorous calculations based on the Mie scattering theory on CSS NPs, we have designed and optimized the dimensions of each layer in the CSS NPs for the double resonance peaks of the CSS NPs with maximal contribution to the enhancement of the hematite PEC activity. Two different NP/hematite architectures on synthesized Sn-doped hematite nanocoral films have been studied – a top-deposited configuration with the optimized CSS NPs on the surface of the hematite, and an embedded configuration with the hematite nanocorals grown over the optimized CSS NPs. Compared with the bare hematite, the average photocurrent density, as a measure of the PEC activity, was found to be improved by 0.6 mA/cm2 and 1.45 mA/cm2 for the top-deposited and embedded CSS NP/hematite configurations, respectively. In particular, the best embedded sample showed an improvement in the photocurrent density from 0.82 mA/cm2 for the bare hematite to 3.0 mA/cm2. This improvement of 2.18 mA/cm2 is one of the highest improvements gained from a plasmonic enhancement strategy for a hematite photoelectrocatalytic system. In addition, the CSS NPs outperformed Au NPs by 1.67 times in the top-deposited configuration and up to 8 times in the embedded configuration. Our simulation and experiment results showed the following key features of CSS NPs which are critical for improving the photocurrent of hematite: (1) a double resonance peak, each of which can contribute separately to the photocurrent, (2) easy tunability of the peaks by varying the dimensions of the CSS NPs and subsequently making the plasmonic peaks strongly scattering or strongly absorbing, thereby optimizing the contributions to the PEC activity of hematite, and (3) spatially uniform electric field distributions which extend 20–25 nm from the outer surface and hence offer potential of increasing carrier generation. Our results show CSS NPs as new and improved plasmonic systems for enhancing PEC performance.