Quantitative probe for in-plane piezoelectric coupling in 2D materials

AbstractPiezoelectric response in two-dimensional (2D) materials has evoked immense interest in using them for various applications involving electromechanical coupling. In most of the 2D materials, piezoelectricity is coupled along the in-plane direction. Here, we propose a technique to probe the in-plane piezoelectric coupling strength in layered nanomaterials quantitively. The method involves a novel approach for in-plane field excitation in lateral Piezoresponse force microscopy (PFM) for 2D materials. Operating near contact resonance has enabled the measurement of the piezoelectric coupling coefficients in the sub pm/V range. Detailed methodology for the signal calibration and the background subtraction when PFM is operated near the contact resonance of the cantilever is also provided. The technique is verified by estimating the in-plane piezoelectric coupling coefficients (d11) for freely suspended MoS2 of one to five atomic layers. For 2D-MoS2 with the odd number of atomic layers, which are non-centrosymmetric, finite d11 is measured. The measurements also indicate that the coupling strength decreases with an increase in the number of layers. The techniques presented would be an effective tool to study the in-plane piezoelectricity quantitatively in various materials along with emerging 2D-materials.

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Sol-Gel Derived PZT Thick Films with Nano-Sized Microstructure

MRS Proceedings ◽

10.1557/proc-748-u14.9 ◽

2002 ◽

Vol 748 ◽

Cited By ~ 1

Author(s):

C. L. Zhao ◽

Z. H. Wang ◽

W. Zhu ◽

O. K. Tan ◽

H. H. Hng

Keyword(s):

Lead Zirconate Titanate ◽

Electromechanical Coupling ◽

Thick Films ◽

Sol Gel ◽

Essential Element ◽

Processing Parameters ◽

Lead Zirconate ◽

Piezoelectric Response ◽

Coupling Coefficients ◽

Pzt Films

ABSTRACTLead zirconate titanate (PZT) films are promising for acoustic micro-devices applications because of their extremely high electromechanical coupling coefficients and excellent piezoelectric response. Thicker PZT films are crucial for these acoustic applications. A hybrid sol-gel technology has been developed as a new approach to realize simple and cost-effective fabrication of high quality PZT thick films. In this paper, PZT53/47 thick films with a thickness of 5–50 μm are successfully deposited on Pt-coated silicon wafer by using the hybrid sol-gel technology. The obtained PZT thick films are dense, crack-free, and have a nano-sized microstructure. The processing parameters of this technology have been evaluated. The microstructure of the film has been observed using field-emission scanning electron microscopy and the crystallization process has been monitored by the X-ray diffraction. The thick films thus made are good candidates for fabrication of piezoelectric diaphragm which will be an essential element of microspeaker and microphone arrays.

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LEAKY SURFACE ACOUSTIC WAVES IN SINGLE-CRYSTAL AlN SUBSTRATE

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156404002922 ◽

2004 ◽

Vol 14 (03) ◽

pp. 837-846 ◽

Cited By ~ 3

Author(s):

GANG BU ◽

DAUMANTAS CIPLYS ◽

MICHAEL S. SHUR ◽

LEO J. SCHOWALTER ◽

SANDRA B. SCHUJMAN ◽

...

Keyword(s):

Single Crystal ◽

Acoustic Waves ◽

Electromechanical Coupling ◽

Surface Acoustic Waves ◽

Propagation Direction ◽

Electromechanical Coupling Coefficient ◽

Coupling Coefficients ◽

Leaky Waves ◽

Temperature Coefficient Of Frequency ◽

Piezoelectric Constants

We report on the velocity V and the electromechanical coupling coefficient K2 of the first and the second leaky surface acoustic waves in various propagation directions in the a-plane AlN single-crystal. For c-propagation direction, the second leaky wave exhibited the velocity of 11016 m/s and K2 of 0.45%. For this direction, the temperature coefficient of frequency was found to be -30 ppm/°C. A near match of the velocities of the plane and leaky waves in the a-plane AlN allowed us to establish analytical relationships between the piezoelectric and elastic constants. A full set of elastic and piezoelectric constants of AlN has been evaluated by fitting the measured and calculated dependencies of velocities and electromechanical coupling coefficients on the propagation direction for both Rayleigh and leaky waves.

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Effect of Bi2O3 Addition on the Microstructure and Electrical Properties of Lead-Free (Na0.5K0.5)NbO3-Bi0.5(Na0.93K0.07)0.5TiO3 Ceramics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.479-480.3 ◽

2013 ◽

Vol 479-480 ◽

pp. 3-7

Author(s):

Chun Huy Wang

Keyword(s):

Solid Solution ◽

Electrical Properties ◽

Electromechanical Coupling ◽

Piezoelectric Properties ◽

Lead Free ◽

Coupling Coefficients ◽

Electromechanical Transducer ◽

Lead Free Ceramics ◽

Thickness Mode ◽

Planar Mode

In the present study, various quantities of Bi2O3were added into 0.98(Na0.5K0.5)NbO3-0.02Bi(Na0.93K0.07)TiO3(0.98NKN-0.02BNKT) ceramics. It was found that 0.98NKN-0.02BNKTwith the addition of 0~0.5 wt.% Bi2O3exhibit relatively good piezoelectric properties. For 0.98NKN-0.02BNKT ceramics, the electromechanical coupling coefficients of the planar modekpand the thickness modektreach 0.40 and 0.47,respectively. For 0.98NKN-0.02BNKT ceramics with the addition of 0.3 wt.% Bi2O3, the electromechanical coupling coefficients ofthe planar modekpand the thickness modektreach 0.50 and 0.53, respectively. It is obvious that 0.98NKN-0.02BNKT solid solution ceramics by adding low quantities of Bi2O3is one of the promising lead-free ceramics for electromechanical transducer applications.

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Electromechanical Coupling of PZT Nanofibers

Volume 13: Nano-Manufacturing Technology; and Micro and Nano Systems, Parts A and B ◽

10.1115/imece2008-68982 ◽

2008 ◽

Author(s):

Shiyou Xu ◽

Yong Shi

Keyword(s):

Forced Vibration ◽

Output Voltage ◽

Electromechanical Coupling ◽

Mechanical Strain ◽

Electrospinning Process ◽

Piezoelectric Response ◽

Vibration Source ◽

Titanium Film ◽

Three Point Bending ◽

Vibration Tests

This paper presented the results of electromechanical characterization of PZT nanofibers through applied mechanical strain and forced vibration. PZT nanofibers were fabricated by electrospinning process. Titanium film with ZrO2 layer was used to collect the nanofibers and also used as the substrates of the test coupons for the bending tests. Mechanical strain was applied to the test coupons through three-point-bending using Dynamic Mechanical Analyzer (DMA). The largest output voltage was 170mV under 0.5% applied strain. Silicon substrate with trenches was also used to collect the PZT nanofibers for the forced vibration tests. The output voltage from 150Hz sinusoid vibration source was also measured. The peaks of the output voltage were 64.9mV and −95.9mV, respectively. These tests have demonstrated the piezoelectric response of PZT nanofibers. Further tests are to be conducted to precisely determine the piezoelectric constants of PZT nanofibers.

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Imaging Mechanism and Quantification of Scanning Probe Microscopies on Ferroelectric Surfaces

MRS Proceedings ◽

10.1557/proc-655-cc7.2.1 ◽

2000 ◽

Vol 655 ◽

Cited By ~ 1

Author(s):

Sergei V. Kalinin ◽

Dawn A. Bonnell

Keyword(s):

Electromechanical Coupling ◽

Variable Temperature ◽

Wide Spectrum ◽

Piezoresponse Force Microscopy ◽

Scanning Probe ◽

Total Charge ◽

Contact Voltage ◽

Domain Structures ◽

Ferroelectric Surfaces ◽

Indentation Problem

AbstractIn the last few years a wide spectrum of non-contact, intermittent contact and contact scanning probe microscopies have been applied to imaging ferroelectric surfaces. The imaging mechanism in non-contact SPM is ultimately related to the total charge distribution on the ferroelectric surface, including both polarization and screening charges. Contact voltage modulation (piezoresponse) force microscopy (PFM) is sensitive to both local polarization via electromechanical coupling and surface charge via capacitive interactions. In the present research we analyze the electrostatic and electromechanical contrast in PFM using analytical solutions for the electrostatic sphere-dielectric plane problem and for the piezoelectric indentation problem. The contribution of electrostatic forces to the image is estimated. Variable-temperature PRI imaging of domain structures in BaTiO3 is performed and the temperature dependence of the piezoresponse is compared with the Ginzburg - Devonshire theory.

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Effect of Electromechanical Coupling on Locally Resonant Metastructures for Simultaneous Energy Harvesting and Vibration Attenuation Applications

Volume 2: Intelligent Transportation/Vehicles; Manufacturing; Mechatronics; Engine/After-Treatment Systems; Soft Actuators/Manipulators; Modeling/Validation; Motion/Vibration Control Applications; Multi-Agent/Networked Systems; Path Planning/Motion Control; Renewable/Smart Energy Systems; Security/Privacy of Cyber-Physical Systems; Sensors/Actuators; Tracking Control Systems; Unmanned Ground/Aerial Vehicles; Vehicle Dynamics, Estimation, Control; Vibration/Control Systems; Vibrations ◽

10.1115/dscc2020-3176 ◽

2020 ◽

Author(s):

Mohammad A. Bukhari ◽

Feng Qian ◽

Oumar R. Barry ◽

Lei Zuo

Keyword(s):

Wave Propagation ◽

Energy Harvesting ◽

Band Structure ◽

Electric Power ◽

External Load ◽

Electromechanical Coupling ◽

Effective Energy ◽

Coupling Coefficients ◽

Vibration Attenuation ◽

Load Resistor

Abstract The study of simultaneous energy harvesting and vibration attenuation has recently been the focus in many acoustic meta-materials investigations. The studies have reported the possibility of harvesting electric power using electromechanical coupling; however, the effect of the electromechanical resonator on the obtained bandgap’s boundaries has not been explored yet. In this paper, we investigate metamaterial coupled to electromechanical resonators to demonstrate the effect of electromechanical coupling on the wave propagation analytically and experimentally. The electromechanical resonator is shunted to an external load resistor to harvest energy. We derive the analytical dispersion curve of the system and show the band structure for different load resistors and electromechanical coupling coefficients. To verify the analytical dispersion relations, we also simulate the system numerically. Furthermore, experiment is carried out to validate the analytical observations. The obtained observations can guide designers in selecting electromechanical resonator parameters for effective energy harvesting from meta-materials.

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