研究目的
To investigate the dependence of resonance frequency behaviors of a clamped circular graphene diaphragm upon opto-mechanical factors including membrane properties, laser excitation parameters, and film boundary conditions in an opto-thermally excited optical fiber Fabry-Perot resonant probe.
研究成果
The opto-thermally excited Fabry-Perot resonant probe with a clamped circular graphene membrane demonstrated that structural properties (radius and thickness), prestress, laser parameters, and boundary conditions significantly influence resonance frequency. Prestress can be linearly tuned via environmental temperature (scale factor 14.2 MPa/K), enhancing linearity in the 10? to 10? Pa range. Laser output power and spot radius affect temperature distribution and frequency, with linear approximations possible in limited ranges. Boundary defects can be mitigated by converting defective circular membranes to double-end clamped beams, improving vibration modes and quality factors. Future work should optimize trade-offs between opto-mechanical parameters and boundary conditions for better resonator performance.
研究不足
The simulation ignored capillary substrate effects and assumed uniform membrane thickness, simplifying the absorption coefficient calculation without using the RF module in COMSOL. This may affect accuracy for non-uniform thickness cases. The study was conducted under vacuum conditions, limiting applicability to real-world environments with air damping. Fabrication challenges, such as imperfect graphene transfer leading to boundary defects, were noted but not fully addressed in simulation.
1:Experimental Design and Method Selection:
The study utilized COMSOL Multiphysics
2:3a simulation software to model a clamped circular graphene membrane under vacuum conditions. The simulation coupled the 'Solid mechanics' module (for deformation sensing) and 'Solid heat transfer' module (for thermal effects) to analyze opto-thermal actuation and resonance characteristics. A 'Swept mesh' was used for element distribution in the thickness direction, and studies included 'Steady state study' and 'Eigen frequency study' to determine resonance behaviors. Sample Selection and Data Sources:
The simulated structure was a clamped circular graphene membrane with parameters such as diameter (50 μm), thickness (
3:35 nm for 10 layers), density (2208 kg/m3), Young's modulus (1 TPa), Poisson's ratio (41), and thermal conductivity (5300 W/(m·K)). Data were generated through parametric sweeps of radius (10–30 μm), thickness (335–35 nm), prestress (103 to 101? Pa), laser output power (1–10 mW), and light spot radius (5–25 μm). List of Experimental Equipment and Materials:
The setup included an optical fiber Fabry-Perot resonant probe with a graphene diaphragm, a distributed feedback (DFB) laser S (wavelength
4:12 nm), an electro-optic modulator (EOM), a lock-in amplifier (HL2FI), an erbium-doped fiber amplifier (EDFA), another DFB laser R (wavelength 72 nm), a 2×1 coupler, a circulator, an optical filter, and a photoelectric detector (PD) with bandwidth 200 MHz and conversion gain 4×10? V/W. An optical spectrum analyzer (AQ6370C, Yokogawa Electric Corporation) was used to confirm cavity length. Experimental Procedures and Operational Workflow:
15 The laser S was modulated by EOM to impose thermal excitation on the graphene membrane, with amplified signals coupled through a 2×1 coupler and delivered to the F-P cavity via a circulator. The detection signal from laser R was filtered and sent to a lock-in amplifier through the PD for resonance signal processing. Simulation involved assigning a Gaussian-distributed heat source based on absorbed heat equations, with temperature and resonance frequency analyzed under varying parameters.
5:Data Analysis Methods:
Data were analyzed using COMSOL simulation outputs, with curve fitting (e.g., linear and polynomial fits) to evaluate relationships between parameters (e.g., temperature vs. radius, frequency vs. prestress). Correlation coefficients and relative errors were calculated to assess fit quality.
独家科研数据包,助您复现前沿成果,加速创新突破
获取完整内容-
Optical Spectrum Analyzer
AQ6370C
Yokogawa Electric Corporation
Used to confirm the initial cavity length of the F-P resonant probe.
-
Simulation Software
COMSOL Multiphysics 5.3a
COMSOL
Used for simulating the opto-thermal and mechanical behaviors of the graphene membrane.
暂无现货
预约到货通知
-
Distributed Feedback Laser
DFB Laser S
Used for opto-thermal excitation of the graphene membrane.
暂无现货
预约到货通知
-
Electro-Optic Modulator
EOM
Modulates the laser S to impose thermal excitation.
暂无现货
预约到货通知
-
Lock-in Amplifier
HL2FI
Used to generate cosine wave modulation and process resonance signals.
暂无现货
预约到货通知
-
Erbium Doped Fiber Amplifier
EDFA
Compensates amplitude attenuation of the modulated laser S.
暂无现货
预约到货通知
-
Distributed Feedback Laser
DFB Laser R
Used for detection of membrane vibration.
暂无现货
预约到货通知
-
Coupler
2×1 Coupler
Optically couples excitation and detection laser signals.
暂无现货
预约到货通知
-
Circulator
Delivers coupled signals to the F-P cavity.
暂无现货
预约到货通知
-
Optical Filter
Filters out excitation light to reserve detection signal.
暂无现货
预约到货通知
-
Photoelectric Detector
PD
Beijing Conquer Optics Science & Technology Co., Ltd
Converts optical detection signals to electrical signals for processing.
暂无现货
预约到货通知
-
登录查看剩余9件设备及参数对照表
查看全部