Browsing by Author "Wang, Yaojin"
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- Dependence of magnetic field sensitivity of a magnetoelectric laminate sensor pair on separation distance: Effect of mutual inductanceLi, Menghui; Wang, Yaojin; Gao, Junqi; Gray, David; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2012-02-01)The effect of mutual inductance on the performance of a pair of Metglas/Pb(Zr,Ti)O-3 laminate magnetoelectric (ME) sensors has been studied. The effective value of the ME coefficient (alpha(ME)) for the laminates was reduced when the distance between was < 40 mm. Separating the two laminates by distances of > 40 mm, the effect of mutual inductance was small. The laminates exhibited the maximum values of alpha(ME). The ME sensor unit with two laminates connected in parallel had higher magnetic field sensitivities. 2012 American Institute of Physics. [doi:10.1063/1.3684986]
- Electric-field induced strain modulation of magnetization in Fe-Ga/Pb(Mg1/3Nb2/3)-PbTiO3 magnetoelectric heterostructuresZhang, Yue; Wang, Zhiguang; Wang, Yaojin; Luo, Chengtao; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2014-02-24)Magnetostrictive Fe-Ga thin layers were deposited on < 110 >-oriented Pb(Mg1/3Nb2/3)-30% PbTiO3 (PMN-30% PT) substrates by pulsed laser deposition. The as-prepared heterostructures showed columnar arrays aligned in the out-of-plane direction. Transmission electron microscopy revealed nanocrystalline regions within the columnar arrays of the Fe-Ga film. The heterostructure exhibited a strong converse magnetoelectric coupling effect of up to 4.55 x 10(-7) s m(-1), as well as an electric field tunability of the in-plane magnetic anisotropy. Furthermore, the remanent magnetization states of the Fe-Ga films can be reversibly and irreversibly changed by external electric fields, suggesting a promising and robust application in magnetic random access memories and spintronics. (C) 2014 AIP Publishing LLC.
- Enhanced magnetoelectric effect in self-stressed multi-push-pull mode Metglas/Pb(Zr,Ti)O-3/Metglas laminatesLi, Menghui; Wang, Yaojin; Gao, Junqi; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2012-07-01)Two methods to effectively induce self-stress on Metglas/Pb(Zr,Ti)O-3/Metglas laminate are presented: (i) applying a dc magnetic field to the Metglas layers or (ii) applying a dc electric field to the core piezoelectric composites. An optimum self-stress enhances the magnetoelectric (ME) effect in the laminates. With a 20 Oe dc magnetic bias, the value of alpha(ME) for the self-stressed laminate was enhanced to 31.4 V/cm center dot Oe, which was by a factor of 1.24x compared to the laminate without self-stress. Furthermore, the equivalent magnetic noise floor was reduced by the self-stress at low frequencies. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4737179]
- Enhanced piezoelectric and ferroelectric properties in Mn-doped Na0.5Bi0.5TiO3-BaTiO3 single crystalsZhang, Qinhui; Zhang, Yaoyao; Wang, Feifei; Wang, Yaojin; Lin, Di; Zhao, Xiangyong; Luo, Haosu; Ge, Wenwei; Viehland, Dwight D. (AIP Publishing, 2009-09-01)High piezoelectric and ferroelectric properties have been found in Mn-doped Na0.5Bi0.5TiO3-BaTiO3 single crystals, which were grown by a top-seeded solution method. The electrical resistivity, dielectric constant, and ferroelectric and piezoelectric properties were all found to be notably enhanced by Mn. The piezoelectric constant d(33) and electromechanical coupling coefficients k(t) and k(31) were found to be as high as 483 pC/N, 0.56, and 0.40, respectively. These values are much higher than those previously reported for Pb-free piezoelectric crystals, demonstrating the real potential for alternative lead-free systems for sensor and piezoelectric applications.
- Enhanced sensitivity to direct current magnetic field changes in Metglas/Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) laminatesGao, Junqi; Shen, Liangguo; Wang, Yaojin; Gray, David; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2011-04-01)We have developed Metglas/Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) magnetoelectric (ME) laminates that have notably larger ME coefficients, with maximum values of up to 45 V/cm Oe. Based on this giant ME effect, the dc magnetic field sensitivity for Metglas/PMN-PT laminate sensors was improved by a factor of > 3, relative to that for Metglas/Pb(Zr,Ti)O(3) (PZT)-based ones of the same geometry. Our new ME sensor can detect dc magnetic field changes as small as (i) 5 nT at 1 kHz and (ii) 1 nT near the resonant frequency in a shield chamber. (C) 2011 American Institute of Physics. [doi:10.1063/1.3569629]
- Enhancement in magnetic field sensitivity and reduction in equivalent magnetic noise by magnetoelectric laminate stacksLi, Menghui; Gao, Junqi; Wang, Yaojin; Gray, David; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2012-05-15)We have investigated the equivalent magnetic noise and magnetic field sensitivity for a magnetoelectric (ME) sensor unit of N numbers of ME laminates stacked together. Our results show with increasing N that the modeled and measured equivalent magnetic noises decreased by a factor of root N and that the magnetic field sensitivities increased by root N. For Metglas/Pb(Mg-1/3,Nb-2/3) O-3-PbTiO3 laminates, the equivalent magnetic noise decreased and the magnetic field sensitivity increased by a factors of 2.1 and 2.3, respectively, for N = 4 relative to that for N = 1. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4718441]
- Flux distraction effect on magnetoelectric laminate sensors and gradiometerShen, Ying; Gao, Junqi; Wang, Yaojin; Hasanyan, Davresh J.; Finkel, Peter; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2013-10-07)A magnetic flux distraction effect caused by a nearby metallic material was investigated for Metglas/Pb(Mg1/3Nb2/3)O-3-PbTiO3 laminated magnetoelectric ( ME) sensors. Using flux distraction, a ME sensor can perform an accurate search for metallic targets of different dimensions at various distances. Detection results and simulations were in good agreement. The findings demonstrate an effective means to employ stationary ME sensors and gradiometers for magnetic search applications. (C) 2013 AIP Publishing LLC.
- Geometry-induced magnetoelectric effect enhancement and noise floor reduction in Metglas/piezofiber sensorsWang, Yaojin; Li, Menghui; Hasanyan, Davresh J.; Gao, Junqi; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2012-08-01)The geometry-dependent magnetoelectric (ME) effect was theoretically and experimentally investigated for multi-push-pull mode Metglas/Pb(Zr,Ti)O-3 sandwich-like laminates. Such structures hold promise for passive sensor applications. A geometry-induced significant enhancement in the ME coefficient and an effective reduction in the equivalent magnetic noise was observed due to an increase in the Metglas width fraction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4737906]
- Giant converse magnetoelectric effect in multi-push-pull mode Metglas/Pb(Zr,Ti)O-3/Metglas laminatesLi, Menghui; Wang, Yaojin; Hasanyan, Davresh J.; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2012-03-01)The converse magnetoelectric (CME) effect was investigated theoretically and experimentally for multi-push-pull mode Metglas/Pb(Zr,Ti)O-3/Metglas laminates. The experimental and theoretical values of the CME coefficient (alpha(B)) exhibited similar trends. A large alpha(B) = 6.94 G/V was observed at 1 kHz under a dc magnetic bias of 11 Oe. At an electromechanical resonance frequency of 29.6 kHz, the laminate exhibited a giant value of alpha(B) = 79.5 G/V. These results show significantly enhanced CME effects in multi-push-pull mode laminates, compared to previously reported ones with different structures and materials. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3698114]
- Giant magnetoelectric effect in self-biased laminates under zero magnetic fieldLi, Menghui; Wang, Zhiguang; Wang, Yaojin; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2013-02-01)A giant magnetoelectric (ME) effect in self-biased annealed Metglas/Pb(Zr,Ti)O-3/Metglas laminates under zero magnetic bias is reported. The remanent magnetization was increased by annealing Metglas, which generated an internal bias field. This shifted the M-H hysteresis loops, yielding large values for the ME voltage coefficient of alpha(ME) = 12 V/cm.Oe and 380 V/cm.Oe at 1 kHz and electromechanical resonance under zero magnetic bias, respectively. This self-biased laminate is shown to have a high sensitivity to ac magnetic fields. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4794056]
- Giant resonant magnetoelectric effect in bi-layered Metglas/Pb(Zr,Ti)O-3 compositesGao, Junqi; Hasanyan, Davresh J.; Shen, Ying; Wang, Yaojin; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2012-11-15)In this paper, giant resonant magnetoelectric (ME) effect in an unsymmetrical bi-layered Metglas/Pb(Zr,Ti)O-3 ME composites with multi-push pull configuration that can be significantly tuned was investigated experimentally and theoretically. The actual measured and predicted results present the similar resonant frequency shifting behaviors for such ME composites: The resonant frequency can be varied from 70 Hz to 220 Hz by tip mass loading, where the ME voltage coefficients were over 250 V/cm-Oe. Moreover, the giant frequency-tunable resonant effect allowed us to design a 60Hz magnetic field energy harvester to be capable of harvesting energy generated by electronic instruments working on a 60Hz ac power supply. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4765724]
- Giant strain with ultra-low hysteresis and high temperature stability in grain oriented lead-free K0.5Bi0.5TiO3-BaTiO3-Na0.5Bi0.5TiO3 piezoelectric materialsMaurya, Deepam; Zhou, Yuan; Wang, Yaojin; Yan, Yongke; Li, Jiefang; Viehland, Dwight D.; Priya, Shashank (Springer Nature, 2015-02-26)We synthesized grain-oriented lead-free piezoelectric materials in (K0.5Bi0.5TiO3-BaTiO3-xNa(0.5)Bi(0.5)TiO(3) (KBT-BT-NBT) system with high degree of texturing along the [001]c (c-cubic) crystallographic orientation. We demonstrate giant field induced strain (similar to 0.48%) with an ultra-low hysteresis along with enhanced piezoelectric response (d(33) similar to 190pC/N) and high temperature stability (similar to 160 degrees C). Transmission electron microscopy (TEM) and piezoresponse force microscopy (PFM) results demonstrate smaller size highly ordered domain structure in grain-oriented specimen relative to the conventional polycrystalline ceramics. The grain oriented specimens exhibited a high degree of non-180 degrees domain switching, in comparison to the randomly axed ones. These results indicate the effective solution to the lead-free piezoelectric materials.
- High non-linear magnetoelectric coefficient in Metglas/PMN-PT laminate composites under zero direct current magnetic biasShen, Ying; Gao, Junqi; Wang, Yaojin; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2014-03-07)The non-linear magnetoelectric (ME) response of Metglas/PMN-PT based sandwiched ME laminate composites has been studied for various thicknesses of the magnetostrictive layer. A significant increase in the non-linear ME coefficient under zero direct current bias was observed with a decreased Metglas thickness ratio for a fixed number of Metglas layers of n = 2. The non-linear ME effect was further improved by driving the laminate at the electromagnetic resonant frequency. The approach offers the potential to modulate low frequency magnetic signals to higher frequencies, where the noise floor is much lower and the signal to noise ratio higher. (C) 2014 AIP Publishing LLC.
- Large field-induced-strain at high temperature in ternary ferroelectric crystalsWang, Yaojin; Chen, Lijun; Yuan, Guoliang; Luo, Haosu; Li, Jiefang; Viehland, Dwight D. (Springer Nature, 2016-10-13)The new generation of ternary Pb(In1/2Nb1/2)O-3-Pb(Mg1/3Nb2/3)O-3-PbTiO3 ferroelectric single crystals have potential applications in high power devices due to their surperior operational stability relative to the binary system. In this work, a reversible, large electric field induced strain of over 0.9% at room temperature, and in particular over 0.6% above 380 K was obtained. The polarization rotation path and the phase transition sequence of different compositions in these ternary systems have been determined with increasing electric field applied along [001] direction based on x-ray diffraction data. Thereafter, composition dependence of field-temperature phase diagrams were constructed, which provide compositional and thermal prospectus for the electromechanical properties. It was found the structural origin of the large stain, especially at higher temperature is the lattice parameters modulated by dual independent variables in composition of these ternary solid solution crystals.
- Mechanical loss and magnetoelectric response in magnetostrictive/interdigitated-electrode/piezoelectric laminated resonatorsWang, Yaojin; Finkel, Peter; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2013-03-28)The mechanical quality factor and the resonant magnetoelectric (ME) response of multi-push-pull mode Metglas/interdigitated (ID)-electrode/Pb(Zr,Ti)O-3 (PZT) ME resonators have been studied as a function of ID-electrode geometry for both sandwich and bimorph configurations. The results show that the mechanical quality factor of the PZT core composite and the effective mechanical quality factor of the ME resonator are increased with increasing ID-electrode spacing. The sandwich resonator was found to exhibit a higher effective mechanical quality factor than the bimorph one. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4798300]
- Modeling of resonant magneto-electric effect in a magnetostrictive and piezoelectric laminate composite structure coupled by a bonding materialHasanyan, Davresh J.; Wang, Yaojin; Gao, Junqi; Li, Menghui; Shen, Ying; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2012-09-15)The harmonic magneto-electro-elastic vibration of a thin laminated composite was considered. A theoretical model, including shear lag and vibration effects was developed for predicting the magneto-electric (ME) effect in a laminate composite consisting of magnetostrictive and piezoelectric layers. To avoid bending, we assumed that the composite was geometrically symmetric. For finite length symmetrically fabricated laminates, we derived the dynamic strain-stress field and ME coefficients, including shear lag and vibration effects for several boundary conditions. Parametric studies are presented to evaluate the influences of material properties and geometries on the strain distribution and the ME coefficient. Analytical expressions indicate that the shear lag and the vibration frequency strongly influence the strain distribution in the laminates and these effects strongly influence the ME coefficients. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4752271]
- Nonlinear magnetoelectric response of a Metglas/piezofiber laminate to a high-frequency bipolar AC magnetic fieldWang, Yaojin; Shen, Ying; Gao, Junqi; Li, Menghui; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2013-03-01)A nonlinear magnetoelectric (ME) response has been investigated in a Metglas/piezofiber laminate by applying a bipolar AC magnetic field (H-ac) without a DC magnetic bias. The ME voltage (V-ME) was measured for various amplitudes of H-ac of up to 9 Oe over the frequency (f) range 0.1
- Piezomagnetic strain-dependent non-linear magnetoelectric response enhancement by flux concentration effectShen, Ying; Gao, Junqi; Wang, Yaojin; Finkel, Peter; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2013-04-01)The non-linear magnetoelectric (ME) effect of Metglas/Pb(Mg1/3Nb2/3)O-3-PbTiO3 heterostructures has been studied. Such effect holds promise for modulation mode ME sensor applications that require no dc bias. The non-linear ME coefficient was found to be highly dependent on the derivative of the piezomagnetic strain coefficient, which could be increased by increasing the Metglas length due to magnetic flux concentration. The non-linear ME coefficient was equal to 9.5V/(cm - Oe(2)) at H-dc = -1 Oe and 7.5V/ (cm - Oe(2)) at H-dc = 0Oe for a structure with 10 cm long Metglas foils. (C) 2013 AIP Publishing LLC.
- Shear-mode magnetostrictive/piezoelectric composite with an enhanced magnetoelectric coefficientWang, Yaojin; Hasanyan, Davresh J.; Li, Jiefang; Viehland, Dwight D.; Luo, Haosu (AIP Publishing, 2012-05-01)A magnetoelectric (ME) laminate heterostructure consisting of two shear-mode piezoelectric Pb(Mg1/3Nb2/3)O-3-30PbTiO(3) (PMN-PT) single crystal layers, a longitudinally magnetized magnetostrictive Tb0.3Dy0.7Fe1.92 alloy plate, and a mechanical clamping brass substrate has been demonstrated that has a notably superior ME effect relative to previous laminate configurations of these two materials. A giant ME coefficient of 7.5 V/(cm Oe) at low frequencies under an optimal dc magnetic bias of similar to 400 Oe was found. The superior ME effects originate from the nature of heterostructure design, which allows the PMN-PT single crystals to operate in a shear mode that has maximum electro-mechanical coupling (i.e., d(15) = 6800 pC/N). (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4718352]
- Structural dependence of nonlinear magnetoelectric effect for magnetic field detection by frequency modulationLi, Menghui; Wang, Yaojin; Shen, Ying; Gao, Junqi; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2013-10-14)The structure differences of magnetoelectric (ME) laminates for passive and active mode sensors are discussed. The Fourier coefficient A(1) calculated from the data of alpha(ME)-H-dc indicates that N = 1 (where N is the number of Metglas layers) should be the optimum structure for the active mode. Experimental investigations of the magnetic field sensitivity agree well with this conjecture. For N = 1, the magnetic field sensitivity was 0.66 nT/Hz(0.5), which was 3.1 times larger than for N = 5. (C) 2013 AIP Publishing LLC.