Browsing by Author "Shen, Ying"

Now showing 1 - 14 of 14
  • Thumbnail Image
    Applications of Magnetoelectric Sensors
    Shen, Ying (Virginia Tech, 2014-02-11)
    The magnetoelectric (ME) effect is an electric output in response to an applied magnetic field. In a heterostructure configuration where the two-phases are engineered with close interface contact, a giant electric response to a magnetic field has been found, which is designated as the ME voltage (or charge) coefficient α^ME. This effect is mediated by a mechanical-coupling between magnetostrictive and piezoelectric phases. In this thesis, I concentrate on application study for ME sensors with respect to noise control and rejection, thermal stability, triple-axis sensor design, array imaging, DC and AC magnetic sources detection and active mode ME sensor development, which is important for future ME sensor device applications.
  • Thumbnail Image
    Direct conversion of chemical energy to mechanical work using a phosphate charged protein
    Shen, Ying (Virginia Tech, 2010-04-09)
    Nature is able to convert chemical energy into mechanical work under modest conditions, i.e., physiological pH and ambient temperature and pressure. One of the most interesting systems is muscle modeled as the "sliding filament" system. The sliding filament system is a combination of a thin actin filament and a thick myosin filament that slide over one another by breaking the "energy-rich" pyrophosphate bond of ATP. The energy from ATP hydrolysis is used for mechanical motion and the energy lost during this process is used to heat our body. In biology, the sliding filament system is taken as a fairly effective model. For engineering systems, the energy lost to heat needs to be reduced to build an efficient energy converter. In our research, we use a phosphate charged protein, casein, and react it with divinyl sulfone (DVS) through a Michael addition reaction to produce a cross-linked gel. The protein gel could be ephosphorylated at standard conditions using bovine phosphatase (bp) and re-phosporylated using casein kinase. When attached to the protein, the negatively charged phosphate groups cause the gel to expand from repulsion. When removed, the protein contracts. Therefore, work is realized without sliding friction, which is the origin of the large energy loss in muscle. FT-IR spectroscopy allows us to follow the two biochemical reactions. We also show a thermodynamic analysis of the work and offer an estimation of the most basic term.
  • Thumbnail Image
    Enhanced dc magnetic field sensitivity by improved flux concentration in magnetoelectric laminates
    Gao, Junqi; Gray, David; Shen, Ying; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2011-10-01)
    In this letter, we present magnetostatic modeling results that show significant magnetic field concentration tunability through geometric modification of high-mu tnagnetostatic Metglas layers of laminate magnetoelectric (ME) sensors. Based on the modeling results, composite ME sensors were fabricated with longer Metglas foils and found to exhibit notably higher ME voltage coefficients at smaller DC magnetic biases in response to a 1 kHz driving signal. Such ME sensors have been used to detect DC magnetic field changes as small as 6 nT at 1 kHz, while maintaining a signal-to-noise ratio greater than 10. This represents an enhancement of similar to 250% relative to values previously reported for Metglas/Pb(Zr,Ti)O(3) laminates. (C) 2011 American Institute of Physics. [doi:10.1063/1.3650713]
  • Thumbnail Image
    Flux distraction effect on magnetoelectric laminate sensors and gradiometer
    Shen, 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.
  • Thumbnail Image
    Giant resonant magnetoelectric effect in bi-layered Metglas/Pb(Zr,Ti)O-3 composites
    Gao, 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]
  • Thumbnail Image
    High non-linear magnetoelectric coefficient in Metglas/PMN-PT laminate composites under zero direct current magnetic bias
    Shen, 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.
  • Thumbnail Image
    Magnetoelectric nonlinearity in magnetoelectric laminate sensors
    Shen, Liangguo; Li, Menghui; Gao, Junqi; Shen, Ying; Li, Jiefang; Viehland, Dwight D.; Zhuang, Xin; Sing, M. Lam Chok; Cordier, Christophe; Saez, Sebastien; Dolabdjian, Christophe (American Institute of Physics, 2011-12-01)
    A nonlinearity in the magnetoelectric coefficient, alpha(Nonlin)(ME), of Metglas/Pb(Zr,Ti)O(3) (PZT) and Metglas/Pb(Mg(1/3),Nb(2/3))O(3)-PbTiO(3) (PMN-PT) laminate sensors has been observed. This nonlinearity was found to be dependent on the dc magnetic bias (H(dc)) and frequency of the ac drive field (H(ac)). The maximum value of alpha(Nonlin)(ME) for both types of composites was found near the electromechanical resonance. For Metglas/PZT laminates, the maximum occurred under a finite bias of H(dc) approximate to 5 Oe; whereas, for Metglas/PMN-PT, the maximum was found near zero dc bias. One application for alpha(Nonlin)(ME) is a cross-modulation scheme that can shift low frequency signals to higher frequency to achieve lower noise floor. For Metglas/PMN-PT, alpha(Nonlin)(ME) has another application: removal of the necessity of a dc bias, which helps to design high-sensitivity sensor arrays and gradiometers. (C) 2011 American Institute of Physics. [doi:10.1063/1.3665130]
  • Thumbnail Image
    Modeling of resonant magneto-electric effect in a magnetostrictive and piezoelectric laminate composite structure coupled by a bonding material
    Hasanyan, 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]
  • Thumbnail Image
    Nonlinear magnetoelectric response of a Metglas/piezofiber laminate to a high-frequency bipolar AC magnetic field
    Wang, 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
  • Thumbnail Image
    Piezomagnetic strain-dependent non-linear magnetoelectric response enhancement by flux concentration effect
    Shen, 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.
  • Thumbnail Image
    Structural dependence of nonlinear magnetoelectric effect for magnetic field detection by frequency modulation
    Li, 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.
  • Thumbnail Image
    Theoretical and experimental investigation of magnetoelectric effect for bending-tension coupled modes in magnetostrictive-piezoelectric layered composites
    Hasanyan, Davresh J.; Gao, Junqi; Wang, Yaojin; Viswan, Ravindranath; Li, Menghui; Shen, Ying; Li, Jiefang; Viehland, Dwight D. (American Institute of Physics, 2012-07-01)
    In this paper, we discuss a theoretical model with experimental verification for the resonance enhancement of magnetoelectric (ME) interactions at frequencies corresponding to bending-tension oscillations. A dynamic theory of arbitrary laminated magneto-elasto-electric bars was constructed. The model included bending and longitudinal vibration effects for predicting ME coefficients in laminate bar composite structures consisting of magnetostrictive, piezoelectric, and pure elastic layers. The thickness dependence of stress, strain, and magnetic and electric fields within a sample are taken into account, as such the bending deformations should be considered in an applied magnetic or electric field. The frequency dependence of the ME voltage coefficients has obtained by solving electrostatic, magnetostatic, and elastodynamic equations. We consider boundary conditions corresponding to free vibrations at both ends. As a demonstration, our theory for multilayer ME composites was then applied to ferromagnetic-ferroelectric bilayers, specifically Metglas-PZT ones. A theoretical model is presented for static (low-frequency) ME effects in such bilayers. We also performed experiments for these Metglas-PZT bilayers and analyzed the influence of Metglas geometry (length and thickness) and Metglas/PZT volume fraction on the ME coefficient. The frequency dependence of the ME coefficient is also presented for different geometries (length, thickness) of Metglas. The theory shows good agreement with experimental data, even near the resonance frequency. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4732130]
  • Thumbnail Image
    Thermal stability of magnetoelectric sensors
    Shen, Ying; Gao, Junqi; Wang, Yaojin; Li, Jiefang; Viehland, Dwight D. (AIP Publishing, 2012-04-01)
    The effect of temperature on the equivalent magnetic noise floor of Metglas-Pb(Zr, Ti)O-3 (PZT) laminate magnetoelectric (ME) sensors has been investigated in the temperature range of -50 degrees C to 50 degrees C. In detail, the parameters that control the noise floor of ME sensors, such as capacitance, tan delta, and ME charge coefficient, were characterized. The results show the noise floor was thermally stable around 30 pT/root Hz (f = 1Hz) over the studied temperature range. To demonstrate the relative invariance of ME sensor at different temperatures over the range studied, a simulation based on a noise model was conducted, where the predicted and measured equivalent magnetic noise floors were found to well agree. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4705298]
  • Thumbnail Image
    Ultralow equivalent magnetic noise in a magnetoelectric Metglas/Mn-doped Pb(Mg1/3Nb2/3)O-3-PbTiO3 heterostructure
    Wang, Yaojin; Gao, Junqi; Li, Menghui; Hasanyan, Davresh J.; Shen, Ying; Li, Jiefang; Viehland, Dwight D.; Luo, Haosu (AIP Publishing, 2012-07-01)
    An ultralow equivalent magnetic noise of 6.2 pT/root Hz at 1 Hz was obtained in a bimorph heterostructure sensor unit consisting of longitudinal-magnetized Metglas layers and a transverse-poled 1 mol. % Mn-doped Pb(Mg1/3Nb2/3)O-3-29PbTiO(3) (PMN-PT) single crystal. Furthermore, the equivalent magnetic noise was <= 1 pT/root Hz at 10 Hz. Compared with previously reported multi-push-pull configuration Metglas/PMN-PT sensor units, the current heterostructure exhibits a higher magnetoelectric coefficient of 61.5 V/(cm x Oe), a similar equivalent magnetic noise at 1 Hz and a lower noise floor at several hertz range. The ultralow equivalent magnetic noise in this sensor unit is due to the low tangent loss and ultrahigh piezoelectric properties of Mn-doped PMN-PT single crystals. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4733963]