Nanobeam Resonator Research Articles

Filling the simulation-to-reality gap: high-degree-of-freedom AI-optimized photonic crystal nanobeam resonators with fabrication tolerance.

In this work, we unveil a novel, to the best of our knowledge, AI-based design method (AIDN1) specifically developed for photonic crystal resonator designs, capable of handling complex designs with over 10 degrees of freedom (DoFs) and considering practical fabrication uncertainties to minimize the common simulation-to-reality (sim2real) gap. Especially, we introduce an ultrashort (<5 µm) curved nanobeam resonator, which obtains an ultrahigh theoretical quality factor (Q-factor) of 2 × 107 and maintains a theoretical Q-factor above 105 even under high fabrication variations. Importantly, we emphasize that AIDN1 is generalizable and our work serves as a solid foundation for future laser fabrication endeavors beyond the realm of ultrashort 1D photonic crystal (PhC) resonators.

Thermoelastic damping analysis for a piezothermoelastic nanobeam resonator using DPL model under modified couple stress theory

Thermoelastic damping analysis for a piezothermoelastic nanobeam resonator using DPL model under modified couple stress theory

Toward Programmable Quantum Processors Based on Spin Qubits with Mechanically Mediated Interactions and Transport.

Solid-state spin qubits are promising candidates for quantum information processing, but controlled interactions and entanglement in large, multiqubit systems are currently difficult to achieve. We describe a method for programmable control of multiqubit spin systems, in which individual nitrogen-vacancy (NV) centers in diamond nanopillars are coupled to magnetically functionalized silicon nitride mechanical resonators in a scanning probe configuration. Qubits can be entangled via interactions with nanomechanical resonators while programmable connectivity is realized via mechanical transport of qubits in nanopillars. To demonstrate the feasibility of this approach, we characterize both the mechanical properties and the magnetic field gradients around the micromagnet placed on the nanobeam resonator. We demonstrate coherent manipulation of a spin qubit in the proximity of a transported micromagnet by utilizing nuclear spin memory and use the NV center to detect the time-varying magnetic field from the oscillating micromagnet, extracting a spin-mechanical coupling of 7.7(9)Hz. With realistic improvements, the high-cooperativity regime can be reached, offering a new avenue toward scalable quantum information processing with spin qubits.

Nonlinear acoustic damping mechanism in micro and nanobeam resonators due to nonlinear shear stress at clamping

Nonlinear acoustic damping mechanism in micro and nanobeam resonators due to nonlinear shear stress at clamping

Exploring regenerative coupling in phononic crystals for room temperature quantum optomechanics

Quantum technologies play a pivotal role in driving transformative advancements across diverse fields, surpassing classical approaches and empowering us to address complex challenges more effectively; however, the need for ultra-low temperatures limits the use of these technologies to particular fields. This work comes to alleviate this problem. We present a way of phononic bandgap engineering using FEM by which the radiative mechanical energy dissipation of a nanomechanical oscillator can be significantly suppressed through coupling with a complementary oscillating mode of a defect of the surrounding phononic crystal (PnC). Applied to an optomechanically coupled nanobeam resonator in the megahertz regime, we find a mechanical quality factor improvement of up to four orders of magnitude compared to conventional PnC designs. As this method is based on geometrical optimization of the PnC and frequency matching of the resonator and defect mode, it is applicable to a wide range of resonator types and frequency ranges. Taking advantage of the, hereinafter referred to as, “regenerative coupling” in phononic crystals, the presented device is capable of reaching f × Q products exceeding 10E16 Hz with only two rows of PnC shield. Thus, stable quantum states with mechanical decoherence times up to 700 μs at room temperature can be obtained, offering new opportunities for the optimization of mechanical resonator performance and advancing the room temperature quantum field across diverse applications.

Damping analysis of a transversely isotropic piezothermoelastic nanobeam resonator based on the MGT thermoelasticity

The present work investigates the vibration of a piezothermoelastic nanobeam in the frame of Moore–Gibson–Thompson (MGT) thermoelasticity theory. Closed form analytical expressions for the thermoelastic damping in terms of quality factor and frequency shift for a homogeneous transversely isotropic piezothermoelastic (PTE) beam is derived by using Euler–Bernoulli beam theory and complex frequency approach. Detailed analysis of damping of vibration owing to thermal fluctuations and electric potential in the present context under three sets of boundary conditions is attempted to investigate the influence of modes of vibration, electric potential, and beam length on energy dissipation caused by thermoelastic damping in PTE beam resonators. Analytical results are illustrated with the help of graphical plots on numerical findings in the case of the nanobeam resonator of Lead Zirconate Titanate (PZT-5A) material. The investigation brings out some significant key findings and observations in view of MGT heat conduction model.

Optically Driven Nano-Beam Resonator for Hydrogen Sensing

Optically Driven Nano-Beam Resonator for Hydrogen Sensing

Implementation of Legendre wavelet method for the size dependent bending analysis of nano beam resonator under nonlocal strain gradient theory

The bending analysis due to thermoelastic loading in nanoscale materials is primarily determined by the physical aspect of the material and the modeling of structures. This paper examines the prediction of bending characteristics of the Euler-Bernoulli beam using Moore-Gibson-Thompson (MGT) thermoelasticity theory in conjunction with nonlocal strain gradient theory (NSGT). The coupled equations for dimensionless deflection and temperature change with ramp-type heating boundary conditions are formulated and solved using the Laplace transform method and the wavelet approximation method. The stiffness softening and hardening effects due to nonlocal and length-scale parameters are assessed, and their discrepancies are discussed. Findings further reveal that the impact of the thermal relaxation parameter on deflection and temperature is negligible. Moreover, the different aspect ratios of the beam's structure depict the prominently behavior of structural simulations in bending.

A high frequency SiC nanobeam resonator with ultra-sensitivity

Nanomechanical resonator based on nanomaterials has great potential for high sensitive, high resolution and negligible energy consumed sensing devices. In this work, high frequency SiC nanobeam resonators with a diameter of ∼100 nm and with lengths of tens of micrometers were designed and demonstrated, which was produced based on the high quality monocrystal 3C-SiC nanowire material with high aspect ratio characteristics. The resonance behaviors of the nanobeam resonator was studied using an integrated mixing circuit measurement system with the pressure from 10−3 to 10−1 Torr. It was observed that the resonant frequency was up to 9.16 MHz, which was a distinguished essential feature for high sensitivity detection. The tunability of SiC nanobeam resonators was about 22%, which can be conveniently controlled by adjusting DC voltage on the gate. It was examined that the detection value of the SiC nanobeam resonator can be as low as zeptogram, which indicated its ultra-sensitive mass detection behaviors. The results show that the SiC nanobeam resonator has high resonant frequency, large tunability and high sensitivity, which is expected to be a high-performance device for biosensing and mechanical sensing.

A Zinc Oxide Nanobeam Resonator for Ultrasensitivity Mass Detection

AbstractNanomechanical resonators are expected to be exceptional sensors for high‐performance mass detection, mechanical sensing, and signal processing. In this paper, zinc oxide nanobeam resonators are produced based on single‐crystal ZnO nanowire, which has a typical diameter down to a few nanometers and the length of hundreds of micrometers. This resonator has the characteristics of high aspect ratio nanobeam structure and reliable material. It is observed that the resonance frequency of ZnO nanobeam resonator is up to 1.47 MHz with a high quality factor of 2300 at room temperature, which will play a key role in high‐sensitivity mass detection. The mass detection of ZnO nanobeam resonator is demonstrated by depositing platinum atoms on the middle of the beam, which shows a sensitivity of 11.13 Hz fg−1 indicating its ultrasensitive mass detection capability. In addition, according to the experiment, the molecular dynamics simulations for the resonator is established, which shows that the detection resolution down to 0.2 yg at room temperature can be realized based on this resonator. The results show that the ZnO nanobeam resonator has enormous potential in ultrasensitive detection for biosensing and gas sensing.

A Size-Dependent Generalized Thermoelasticity Theory for Thermoelastic Damping in Vibrations of Nanobeam Resonators

Thermoelastic damping (TED) has been discerned as a definite source of intrinsic energy loss in miniaturized mechanical elements. The size-dependent structural and thermal behavior of these small-sized structures has been proven through experimental observations. As a first attempt, this article exploits nonlocal strain gradient theory (NSGT) and nonlocal dual-phase-lag (NDPL) heat conduction model simultaneously to acquire a mathematical formulation and analytical solution for TED in nanobeams that can accommodate size effect into both structural and heat transfer fields. For this purpose, the coupled equations of motion and heat conduction are firstly extracted via NSGT and NDPL model. Next, by deriving the distribution of temperature from heat conduction equation and substituting it in the motion equation, the unconventional thermoelastic frequency equation is established. By deriving the real and imaginary parts of the frequency from this equation and employing the definition of quality factor, an explicit solution is given for approximating TED value. The veracity of the proposed model is checked by comparing it with the solutions reported in the literature for specific and simpler cases. A diverse set of numerical results is then presented to appraise the influence of some factors like structural and thermal nonlocal parameters, strain gradient length scale parameter, geometrical parameters, mode number and material on the amount of TED. According to the results, use of NDPL model yields a smaller value for TED than DPL model, but prediction of NSGT about the magnitude of TED, in addition to the relative amounts of its two scale parameters, strongly depend on other factors such as aspect ratio, vibration mode and material type.

Study on the Acousto-Optic Coupling Effect of a One-Dimensional Hetero-Optomechanical Crystal Nanobeam Resonator

The optomechanical crystal nanobeam resonator has attracted the attention of researchers due to its high optomechanical coupling rate and small modal volume. In this study, we propose a high-optomechanical-coupling-rate heterostructure with a gradient cavity, and the optomechanical rates of the single mirror and hetero-optomechanical crystal nanobeam resonators are calculated. The results demonstrate that the heterostructure based on the utilization of two mirror regions realizes better confinement of the optical and mechanical modes. In addition, the mechanical breathing mode at 9.75 GHz and optical mode with a working wavelength of 1.17 μm are demonstrated with an optomechanical coupling rate g0 = 3.81 MHz between them, and the mechanical quality factor is increased to 3.18 × 106.

Thermoelastic damping analysis in nanobeam resonators considering thermal relaxation and surface effect based on the nonlocal strain gradient theory

With the extensive applications of the micro/nano-electro-mechanical systems, a great deal of attention has been paid to explore the influences of the arising size-dependent effect and surface effect on their performance. Along with these effects, the nonlocal elasticity, strain gradient theory, and surface elasticity theory were successively proposed. Moreover, it is inevitable for MEMS/NEMS to work in a variable temperature environment, correspondingly, the thermal-induced stress or deformation becomes another issue that needs serious concern. Thermoelastic damping (TED), as a main energy dissipation source, is a major challenge in designing higher-quality factor resonators. However, considering the thermoelastic coupling effect, the aforementioned theories are not capable enough to depict the thermoelastic performance of micro/nano-resonators. To amend this deficiency, based on nonlocal strain gradient theory, a new model for assessing the TED of nanobeam resonators by incorporating the thermal relaxation effect and the surface effect is developed. The corresponding governing equations for the Euler–Bernoulli microbeam resonator model are formulated, and then, solved by means of a complex frequency method. The influences of the nonlocal parameter, strain gradient coefficients, aspect ratio, surface stress and surface elasticity on the TED are examined and discussed in detail.

Nonlocal thermoelastic waves inside nanobeam resonator subject to various loadings

The present article focuses on the new meticulous model based on the postulate of memory-dependent derivatives to analyze the thermo-mechanical interactions inside the nano-beam-based machined resonators. Also, the size effect on dynamic responses of thermoelastic vibrations of homogeneous and isotropic nano-beam is considered. The fundamental expressions are formulated in the frame of non-local generalized thermoelasticity with paired relaxation times by operating the results of Euler-Bernoulli beam theory, non-local effect, and memory-dependent derivative. The proposed model is applied to study the nano-beam-based machined resonator subjected to the ramp-type heating and exponentially decaying time-dependent load. Closed-form solutions of the physical fields are examined by applying the Laplace transform mathematical mechanism. However, the coherence of the new thermal conductivity framework, a collation has been bestowed among the results obtained in the presence or absence of the memory-dependent derivative; also, the size effect is analyzed on the significant parameters of nano-beam such as deflection, temperature, displacement as well as bending moment. Moreover, the prominent influence of the distinct affecting parameters such as constituents of memory-dependent derivative (kernel function and time delay) and ramping time parameter with an applied load on the physical fields have been investigated with the help of quantitative results.

Nanomechanical design strategy for single-mode optomechanical measurement

The motion of a mechanical resonator is intrinsically decomposed over a collection of normal modes of vibration. When the resonator is used as a sensor, its multimode nature often deteriorates or limits its performance and sensitivity. This challenge is frequently encountered in state-of-the-art optomechanical sensing platforms. We present a mechanical design strategy that ensures that optomechanical measurements can retrieve information on a single mechanical degree of freedom, and implement it in a sliced photonic crystal nanobeam resonator. A spectral design approach is used to make mechanical symmetries robust against practical disorder. The effectiveness of the method is evaluated by deriving a relevant figure of merit for continuous and pulsed measurement application scenarios. The method can be employed in any mechanical design that presents unwanted spurious mechanical modes. In the nanobeam platform, we experimentally show an increase of the signal to noise ratio of the mode of interest over the first spurious mode by four orders of magnitudes.

Size-dependent thermoelastic damping analysis in nanobeam resonators based on Eringen’s nonlocal elasticity and modified couple stress theories

Thermoelastic damping has emerged as a critical issue in the modeling and design of micro and nanomechanical systems. Therefore, an extensive research interest is being devoted towards the reduction in thermoelastic damping for micro and nanomechanical systems. The present study intends to examine thermoelastic damping in nanobeam resonators using the modified couple stress theory and Eringen’s nonlocal elasticity theory, thus so-called modified nonlocal couple stress theory within the context of the recently proposed Moore–Gibson–Thompson thermoelasticity theory. In order to observe size effects, the size-dependent coupled thermoelastic equations are derived by combining modified couple stress theory and nonlocal elasticity theory in the frame of Moore–Gibson–Thompson thermoelasticity. The coupled governing equations for thermoelastic damping of nanobeam resonators are solved analytically in terms of the inverse quality factor. The size-dependent thermoelastic damping of nanobeams is presented graphically with the help of numerical results predicted by modified nonlocal couple stress theory. The results obtained under the combined effects of modified couple stress theory and nonlocal theory in the present context are further compared to those of the classical, modified couple stress, and nonlocal elasticity theories as special cases of the modified nonlocal couple stress theory. It is observed that thermoelastic damping weakens at the submicron scale under Eringen’s nonlocal elasticity theory, whereas it becomes greater at the submicron scale under modified couple stress theory. However, at the submicron scale, the modeling of nanobeam resonators using modified nonlocal couple stress theory reveals a smaller amount of thermoelastic damping than modified couple stress, nonlocal, and classical theories. In addition, as compared to the Green–Naghdi thermoelasticity theory of type III (GN-III), the Moore–Gibson–Thompson model predicts a higher thermoelastic damping value, while agreeing with the results predicted by the Lord–Shulman (LS) model under modified nonlocal couple stress theory. Some important points highlighted here are believed to be useful in the design of mechanical resonators at micron and submicron scales.

Lateral vibration of an axially moving thermoelastic nanobeam subjected to an external transverse excitation

&lt;abstract&gt; &lt;p&gt;This paper gives a mathematical formulation for the transverse resonance of thermoelastic nanobeams that are simply supported and compressed with an initial axial force. The nonlocal elasticity concept is used to analyze the influence of length scale with the dual-phase-lag (DPL) heat transfer theory. The nanobeam is due to a changing thermal load and moves in one direction at a constant speed. The governing motion equation for the nonlocal Euler-Bernoulli (EB) beam hypothesis can also be derived with the help of Hamilton's principle and then solved by means of the Laplace transform technique. The impacts of nonlocal nanoscale and axial velocity on the different responses of the moving beam are investigated. The results reveal that phase delays, as well as the nonlocal parameter and external excitation load, have a substantial impact on the system's behavior.&lt;/p&gt; &lt;/abstract&gt;

Compact high-contrast silicon optical filter using all-passive and CROW Fano nanobeam resonators.

We propose and experimentally demonstrate a high-order coupled-resonator optical waveguide (CROW) nanobeam filter with semi-symmetrical Fano resonance enhancement. Thanks to the tight arrangement of multiple nanobeams and assistance of the partial transmission element, the designed filter has a high-contrast transmission and low insertion loss. Finally, the fabricated filter has a compact size of 20µm×10µm, a high extinction ratio as much as 70 dB, and an insertion loss as low as 1 dB. This filter shows a passive structure without thermal control configuration for calibration on each resonator. This compact filter can be a basic building block for various applications requiring high extinction ratio filtering, such as single-photon source filtering of integrated photon chips.

Effect of two-temperature parameter on thermoelastic vibration in micro and nano beam resonator

Thermoelastic vibration of micro and nano-beam resonators is described by the Euler-Bernoulli beam theory in context with two-temperature generalized thermoelasticity theory. The amplitude of deflection and thermal moment in the case of simply supported and the isothermal beam are obtained by the Laplace transform method along with the finite Fourier sine transform method and the vibration frequency is examined by the normal mode analysis when the beam-ends are clamped and isothermal. The effects of the two-temperature parameter and micro and nano-beam thickness on the amplitude of deflection, thermal moment, and thermoelastic vibration frequency of the micro and nano-beam resonator have been studied and shown with the numerical results. A comparison of the results with the corresponding results of the two-temperature generalized thermoelasticity (2TLS) and the Lord-Shulman (LS) theories is also presented. Besides, the size dependency nature of the micro and nano-beam is analyzed by analytical and numerical results.

Study of transversely isotropic nonlocal thermoelastic thin nano-beam resonators with multi-dual-phase-lag theory

This study deals with a novel model of forced vibrational analysis of nonlocal transversely isotropic thermoelastic nanobeam resonators due to ramp-type heating and due to time varying exponentially decaying load with multi-dual-phase-lag theory of thermoelasticity. The mathematical model is prepared for the nanobeam in a closed form with the application of Euler–Bernoulli (E–B) beam theory using nonlocal generalized thermoelasticity with multi-dual phase lags. The nonlocal nanobeam theory has a nonlocal parameter to depict small-scale effect. The Laplace Transform technique has been used to find the expressions for lateral deflection, conductive temperature, thermal moment, nonlocal axial stress and thermodynamic temperature for (i) clamped–clamped, (ii) simply supported–simply supported, (iii) clamped–simply supported, (iv) clamped–free, and (v) free–free nanobeam in the transformed domain. The general algorithm of the inverse Laplace Transform is developed to compute the results numerically in physical domain. The results exhibit that the amplitude of deflection and thermal moment is attenuated and depends upon the schematic design of the nanobeam being considered. Also, it can be found from both the numerical calculations and the analytic results that nonlocal multi-dual-phase-lag theory of thermoelasticity with two temperatures due to time varying exponentially decaying load has significant effect on deflection and thermal moment. The effect of different theories of nonlocal thermoelasticity, due to time varying exponentially decaying load, has been depicted on the various quantities. Some particular cases have also been deduced.