We have derived a general formula for sensitivity optimization of gravimetric sensors and have used it to design a high sensitivity gravimetric sensor using unidirectional carbon fiber epoxy composite （CFEC） wavegui...We have derived a general formula for sensitivity optimization of gravimetric sensors and have used it to design a high sensitivity gravimetric sensor using unidirectional carbon fiber epoxy composite （CFEC） waveguide layer on （1 -x）Pb（Znl/3Nbz/3）O3-xPbTiO3 （PZN-xPT） single crystal substrate with the carbon fibers parallel to the xj and x2 axes, respectively. The normalized maximum sensitivity （｜sfm｜λ）max exhibits an increasing tendency with the decrease of （h/λ）opt and the maximum sensitivity （｜sfm｜λ）max increases with the elastic constant c6E6 of the piezoelectric substrate material. For the CFEC/[011]c poled PZN-7%PT single crystal sensor configuration, with the carbon fibers parallel to the xa axis at λ = 24 ktm, the maximum sensitivity ｜sfm｜max can reach as high as 1156 cmZ/g, which is about three times that of a traditional SiO2/ST quartz structure gravimetric sensor. The better design selection is to have the carbon fibers parallel to the direction of propagation of Love wave in order to obtain the best sensitivity.展开更多
Dispersion relations of Love mode acoustic guided 0.33 PT） single crystal with a gold electrode film waves propagation in Pb（Mg1/3 Nb2/3 ） 03-33%PbTiO3 （PMN- are calculated. There is no cross coupling among Love w...Dispersion relations of Love mode acoustic guided 0.33 PT） single crystal with a gold electrode film waves propagation in Pb（Mg1/3 Nb2/3 ） 03-33%PbTiO3 （PMN- are calculated. There is no cross coupling among Love wave modes, which is conducive to eliminating the cross interference between modes. The general formula is derived to precisely measure the thickness of the electrode. More acoustic energy would be concentrated inside the electrode with the increase of film thickness for a given frequency. Compared with the PZT-5 ceramic, [001]c poled PMN- 33%PT single crystal has a slower attenuation of the amplitude of the acoustic guided wave. Therefore, single crystal is extremely suitable for making low loss acoustic wave devices with a high operating frequency.展开更多
Surface acoustic wave (SAW) propagation in relaxor-based ferroelectric single crystals 0.93Pb(Zn_(1/3)Nb_(2/3))O_(3)- 0.07Pb TiO_(3) (PZN- 7%PT ) poled along [011]c has been analyzed theoretically.The results show tha...Surface acoustic wave (SAW) propagation in relaxor-based ferroelectric single crystals 0.93Pb(Zn_(1/3)Nb_(2/3))O_(3)- 0.07Pb TiO_(3) (PZN- 7%PT ) poled along [011]c has been analyzed theoretically.The results show that PZN- 7% PT single crystals have excellent SAW properties,such as low phase velocities,very high electromechanical coupling coefficients and small power flow angles.It is also found that the SAW properties strongly depend on the propagation direction and the characteristic curves of SAW phase velocity,and the electromechanical coupling coefficients are symmetric with respect to θ =90°.Considering all related factors,the X-cut PZN-7%oPT single crystal has the best performance.Based on our results,the X-cut PZN-7%PT single crystals poled along [011]c are an excellent candidate for ultra-wide bandwidth low-frequency SAW devices.展开更多
Surface acoustic wave （SAW） properties at the x-cut of relaxor-based 0.67Pb（Mg1/3Nb2/3）O3-0.33PbTiO3 （PMN- 33%PT） ferroelectric single crystals are analyzed theoretically when poled along the [001]c cubic direct...Surface acoustic wave （SAW） properties at the x-cut of relaxor-based 0.67Pb（Mg1/3Nb2/3）O3-0.33PbTiO3 （PMN- 33%PT） ferroelectric single crystals are analyzed theoretically when poled along the [001]c cubic direction. It can be found that PMN-33%PT single crystal is a kind of material with a low phase velocity and high electromechanical coupling coefficient, and the single crystal possesses some cuts with zero power flow angle. The results are based on the material parameters at room temperature. The conclusions provide device designers with a few ideal cuts of PMN-33%PT single crystals. Moreover, choosing an optimal cut will dramatically improve the performance of SAW devices, and corresponding results for crystal systems working at other temperatures could also be figured out by employing the method.展开更多
The influence of temperature on mode coupling effect in piezoelectric vibrators remains unclear.In this work,we discuss the influence of temperature on two-dimensional(2D)mode coupling effect and electromechanical cou...The influence of temperature on mode coupling effect in piezoelectric vibrators remains unclear.In this work,we discuss the influence of temperature on two-dimensional(2D)mode coupling effect and electromechanical coupling coefficient of cylindrical[001]c-poled Mn-doped 0.24PIN-0.46PMN-0.30PT piezoelectric single-crystal vibrator with an arbitrary configuration ratio.The electromechanical coupling coefficient kt decreases with temperature increasing,whereas k33 is largely invariant in a temperature range of 25℃-55℃.With the increase of temperature,the shift in the‘mode dividing point’increases the scale of the poling direction of the piezoelectric vibrator.The temperature has little effect on coupling constantΓ.At a given temperature,the coupling constantΓof the cylindrical vibrator is slightly greater than that of the rectangular vibrator.When the temperature changes,the applicability index(M)values of the two piezoelectric vibrators are close to 1,indicating that the coupling theory can be applied to piezoelectric vibrators made of late-model piezoelectric single crystals.展开更多
基金Supported by the NSFC(Grant No.50602009 ,50972034)Program of the Ministry of Education of China for New Cen-tury Excellent Talents in University(Grant No.NCET-06-0345)+1 种基金Postdoctoral Science Research Developmental Foun-dation of Heilongjiang Province (Grant No.LBH-Q06068)SRF for ROCS,SEMand NI H(Grant No.P41-EB21820)
基金supported by the National Basic Research Program of China(Grant No.2013CB632900)
文摘We have derived a general formula for sensitivity optimization of gravimetric sensors and have used it to design a high sensitivity gravimetric sensor using unidirectional carbon fiber epoxy composite （CFEC） waveguide layer on （1 -x）Pb（Znl/3Nbz/3）O3-xPbTiO3 （PZN-xPT） single crystal substrate with the carbon fibers parallel to the xj and x2 axes, respectively. The normalized maximum sensitivity （｜sfm｜λ）max exhibits an increasing tendency with the decrease of （h/λ）opt and the maximum sensitivity （｜sfm｜λ）max increases with the elastic constant c6E6 of the piezoelectric substrate material. For the CFEC/[011]c poled PZN-7%PT single crystal sensor configuration, with the carbon fibers parallel to the xa axis at λ = 24 ktm, the maximum sensitivity ｜sfm｜max can reach as high as 1156 cmZ/g, which is about three times that of a traditional SiO2/ST quartz structure gravimetric sensor. The better design selection is to have the carbon fibers parallel to the direction of propagation of Love wave in order to obtain the best sensitivity.
文摘Dispersion relations of Love mode acoustic guided 0.33 PT） single crystal with a gold electrode film waves propagation in Pb（Mg1/3 Nb2/3 ） 03-33%PbTiO3 （PMN- are calculated. There is no cross coupling among Love wave modes, which is conducive to eliminating the cross interference between modes. The general formula is derived to precisely measure the thickness of the electrode. More acoustic energy would be concentrated inside the electrode with the increase of film thickness for a given frequency. Compared with the PZT-5 ceramic, [001]c poled PMN- 33%PT single crystal has a slower attenuation of the amplitude of the acoustic guided wave. Therefore, single crystal is extremely suitable for making low loss acoustic wave devices with a high operating frequency.
基金Supported by the National Natural Science Foundation of China under Grant No 50972034the Program of the Ministry of Education of China for New Century Excellent Talents in University under Grant No NCET-06-0345+1 种基金the Postdoctoral Science Research Developmental Foundation of Heilongjiang Province under Grant No LBH-Q06068the Program of BRET and Excellent Team in Harbin Institute of Technology,SRF for ROCS,SEM,and NIH under Grant No P41-EB21820.
文摘Surface acoustic wave (SAW) propagation in relaxor-based ferroelectric single crystals 0.93Pb(Zn_(1/3)Nb_(2/3))O_(3)- 0.07Pb TiO_(3) (PZN- 7%PT ) poled along [011]c has been analyzed theoretically.The results show that PZN- 7% PT single crystals have excellent SAW properties,such as low phase velocities,very high electromechanical coupling coefficients and small power flow angles.It is also found that the SAW properties strongly depend on the propagation direction and the characteristic curves of SAW phase velocity,and the electromechanical coupling coefficients are symmetric with respect to θ =90°.Considering all related factors,the X-cut PZN-7%oPT single crystal has the best performance.Based on our results,the X-cut PZN-7%PT single crystals poled along [011]c are an excellent candidate for ultra-wide bandwidth low-frequency SAW devices.
基金Supported in part by the National Natural Science Foundation of China under Grant No 50602009, the New Century Excellent Talent Project （NCET） of the Ministry of Education of China under Grant No NCET-06-0345, the Postdoctoral Science Research Developmental Foundation of Heilongjiang Province under Grant No LBH-Q06068, and the NIH under Grant No P41-EB21820.
文摘Surface acoustic wave （SAW） properties at the x-cut of relaxor-based 0.67Pb（Mg1/3Nb2/3）O3-0.33PbTiO3 （PMN- 33%PT） ferroelectric single crystals are analyzed theoretically when poled along the [001]c cubic direction. It can be found that PMN-33%PT single crystal is a kind of material with a low phase velocity and high electromechanical coupling coefficient, and the single crystal possesses some cuts with zero power flow angle. The results are based on the material parameters at room temperature. The conclusions provide device designers with a few ideal cuts of PMN-33%PT single crystals. Moreover, choosing an optimal cut will dramatically improve the performance of SAW devices, and corresponding results for crystal systems working at other temperatures could also be figured out by employing the method.
基金Project supported by the Basic Scientific Research Foundation of College and University in Heilongjiang Province,China(Grant No.2018QNL-16)the Guiding Science and Technology Project of Daqing City(GSTPDQ),China(Grant No.zd-2019-03)the National Natural Science Foundation of China(Grant Nos.11304061 and 51572056).
文摘The influence of temperature on mode coupling effect in piezoelectric vibrators remains unclear.In this work,we discuss the influence of temperature on two-dimensional(2D)mode coupling effect and electromechanical coupling coefficient of cylindrical[001]c-poled Mn-doped 0.24PIN-0.46PMN-0.30PT piezoelectric single-crystal vibrator with an arbitrary configuration ratio.The electromechanical coupling coefficient kt decreases with temperature increasing,whereas k33 is largely invariant in a temperature range of 25℃-55℃.With the increase of temperature,the shift in the‘mode dividing point’increases the scale of the poling direction of the piezoelectric vibrator.The temperature has little effect on coupling constantΓ.At a given temperature,the coupling constantΓof the cylindrical vibrator is slightly greater than that of the rectangular vibrator.When the temperature changes,the applicability index(M)values of the two piezoelectric vibrators are close to 1,indicating that the coupling theory can be applied to piezoelectric vibrators made of late-model piezoelectric single crystals.
