SCIENCE CHINA Technological Sciences

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*Corresponding author (email: zhouji@mail.tsinghua.edu.cn)

October 2013 Vol.56 No.10: 2572–2575 doi: 10.1007/s11431-013-5335-x

Magnetoelectric cylindrical layered composite structure with multi-resonance frequencies

BI Ke1, DONG GuoYan2, PAN DeAn3 & ZHOU Ji1*

1 State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China;

2 College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China; 3 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China

Received February 26, 2013; accepted August 7, 2013; published online September 6, 2013

A combined ME composite structure is made of several cylindrical layered composites in series or parallel connection. Due to the cylindrical structure, the combined structure does not need more space. The characteristics of multi-resonance frequencies have been studied. Each resonance frequency of the structure can be adjusted by changing the cylinder diameter of the corre-sponding cylindrical layered composites. The number of resonance frequencies increases as the number of cylindrical layered composites increases. The multi-resonance frequencies behavior makes these cylindrical layered composite structures suitable for applications in multifuctional devices with multi-frequencies operation.

functional composites, magnetoelectric, multi-resonance frequencies

Citation: Bi K, Dong G Y, Pan D A, et al. Magnetoelectric cylindrical layered composite structure with multi-resonance frequencies. Sci China Tech Sci, 2013, 56: 25722575, doi: 10.1007/s11431-013-5335-x

1 Introduction

The magnetoelectric (ME) effect is defined as an electric polarization induced by an applied magnetic field and vice versa [1, 2]. Single phase ME materials are not recognized as practically viable materials for device application due to their low Curie temperatures below the room temperature and the effect is usually weak [3, 4]. Because of strong ME effect at room temperature, ME composite materials com-bining ferromagnetic and ferroelectric phases have recently stimulated tremendous theoretical and experimental inter-ests for use as sensors, actuators and transducers [5–11]. Layered ME composites, the main focus of ME composite materials, possess strong ME coupling due to their giant product effect of the magnetostrictive and piezoelectric ef-

fects [12, 13]. The ME coefficient E of the layered ME composites can reach a value of 400 V cm1 Oe1 [14].

The ME coupling in layered composites of magnetostric-tive and piezoelectric phases is mediated by mechanical deformation [15]. In a bias magnetic field, there is defor-mation of the magnetostrictive phases due to magnetostric-tive effect. A superimposed ac magnetic field then gives rise to a pesudopiezomagnetic effect, which produces dynamic deformation passed along the piezoelectric layer by inter-face coupling, leading to an ac electric field across the pie-zoelectric phases [16]. Hence, the ME effect of layered composites depends strongly on the ac magnetic field fre-quency. When the layered ME composites undergo the res-onance frequency, the ME effect would be greatly enhanced, which is related to electromechanical resonance for the pie-zoelectric phases [17, 18]. There are one or two resonance frequencies for layered ME composites when the ac mag-netic filed frequency varies from 1 to 150 kHz [19–21].

Bi K, et al. Sci China Tech Sci October (2013) Vol.56 No.10 2573

How to design ME composites with multi-resonance fre-quencies in order to realize the wideband ME effect is an important research topic. However, there are few reports on it.

In this work, we designed a combined ME composite structure with multi-resonance frequencies. As the compo-nents of the combined ME composite structure, several Ni/PZT/Ni cylindrical layered composites connected in a series or parallel mode. There are two merits for cylindrical layered composites used in the multi-frequencies structure. First, the resonance frequency of cylindrical layered com-posites can be controlled by changing the cylinder diameter [22]. Second, due to the cylindrical structure, the combined structure does not need more space. Cylindrical layered composites can link with one another—cylinder within cyl-inder.

2 Experimental

The Ni/PZT/Ni cylindrical layered composites were pre-pared by electroless deposition. The preparation process and Ni/PZT/Ni cylindrical layered composites are described in details elsewhere [22]. The sketch diagram of Ni/PZT/Ni cylindrical layered composites is shown in Figure 1(a). The dimensions of the hollow Pb(Zr,Ti)O3 (PZT) cylinders are 22 mm×23 mm×5 mm, 28 mm×29 mm×5 mm, 34 mm×35 mm×5 mm (D1×D2×h), where D1 is the inner diameter, D2 is the corresponding outer diameter, and h is the height. The total thickness of the Ni layers is approximately 100 µm and identical for all the composites. The proposed structure is made of several Ni/PZT/Ni cylindrical layered composites

Figure 1 The geometry arrangements of (a) the Ni/PZT/Ni cylindrical layered composites, and the combined ME composite structure in (b) series and (c) parallel modes.

in series or parallel connection. The geometry arrangements of the combined ME composite structures in series and par-allel modes are shown in Figures 1(b) and (c), respectively.

The ME effect of the combined ME composite structure is measured by applying both constant (Hdc) and alternating (H) magnetic fields perpendicular (vertical mode) to the cylinder axis direction. The induced voltage signal V across the structure is amplified and measured by an oscil-loscope. The dc bias magnetic field Hdc could be changed in the range 0–8 kOe. The superimposed ac magnetic field H is generated by Helmholtz coils, and the ac magnetic field frequency f is varied from 1 to 150 kHz. The ME voltage coefficient is calculated based on E,V = V/(tPZTH), where tPZT is the thickness of the PZT layer. In this experiment, H = 1.2 Oe as the amplitude of the ac current through the coil is equal to 1 A.

3 Results and discussion

For layered ME composites consisting of mechanically coupled magnetostrictive and piezoelectric layers, the reso-nance frequency of the cylindrical composites is associated with the magnetomechanical resonance of the magnetostric-tive layers and the electromechanical resonance of the pie-zoelectric layers [17]. The resonance frequency of Ni/PZT/ Ni cylindrical layered composites is given by [22]

r11

1 1 ,fD s

(1)

where fr is the resonance frequency, D is the average cylin-der diameter, is the average density, the equivalent

elastic compliance 11s is given by

Ni PZT11 11

11 PZT NiNi 11 PZT 11

,s s

sv s v s

(2)

where Ni11s and PZT

11s are the respective elastic complianc-

es of Ni and PZT layers, vNi and vPZT are the volume frac-tions, respectively.

Using eqs. (1) and (2), one can predict the resonance frequencies of Ni/PZT/Ni cylindrical layered composites with the average cylinder diameters D=22.5, 28.5, 34.5 mm to be 45.3, 35.7, 29.5 kHz. The parameters for the predic-

tion are =7.8×103 kg m3; Ni11s = 4.65×1012 m2 N1;

PZT11s =15 ×1012 m2 N1.

Figure 2 shows the ME voltage coefficient (E,V) de-pendences on ac magnetic field frequency f at Hdc=150 Oe for the Ni/PZT/Ni cylindrical layered composites with a series of average cylinder diameter D. First, for all the cases, there is one resonance peak for 1<f<150 kHz. Second, the resonance frequency decreases with the increasing cylinder

2574 Bi K, et al. Sci China Tech Sci October (2013) Vol.56 No.10

Figure 2 Magnetoelectric voltage coefficient E,V dependences on ac magnetic field frequency f at Hdc =150 Oe for the Ni/PZT/Ni cylindrical layered composites with a series of average cylinder diameter D.

diameter. Third, the resonance frequencies of Ni/PZT/Ni cylindrical layered composites with the average cylinder diameters D = 22.5, 28.5, 34.5 mm are 46.0, 35.8, 29.8 kHz, respectively. The experimental results are in good agree-ment with the predicted ones. In addition, the maximum ME voltage coefficient increases with the increasing cylinder diameter, which agrees well with that observed in ref. [22]. From the above data one can infer that the resonance fre-quency can be controlled by changing the cylinder diameter.

ME voltage coefficient E,V dependences on ac magnetic field frequency f at Hdc=150 Oe for the combined ME com-posite structure are shown in Figure 3. The combined ME composite structure is made of two cylindrical layered composites in series or parallel connection, and the average cylinder diameters D of the two cylindrical layered compo-sites are 22.5 and 28.5 mm, respectively. From Figure 3, there are two resonance peaks for 1<f<150 kHz. The first and second resonance frequencies of the proposed structure are 35.6 and 46.0 kHz, which agree well with those of the corresponding cylindrical layered composites. According to the analysis mentioned above, the cylindrical layered com-posites with different average cylinder diameters have dif-ferent resonance frequency. When the combined ME com-posite structure undergoes the resonance frequency of one cylindrical layered composites, the first peak appears. As the f increases further, the second peak appears when the proposed structure undergoes the resonance frequency of the other cylindrical layered composites. Therefore, each resonance frequency of the structure can be adjusted by changing the cylinder diameter of the corresponding cylin-drical layered composites.

Comparing the data from Figure 3(a) with that from Fig-ure 3(b), one can see that the maximum ME voltage coeffi-cient of the combined ME composite structure in the series mode is larger than that of the combined ME composite structure in the parallel mode. As the bias and ac magnetic fields applied to the combined ME composite structure in a series or parallel mode, the induced voltage signal V of each cylindrical layered composites with the same D is

Figure 3 Magnetoelectric voltage coefficient E,V dependences on ac magnetic field frequency f at Hdc=150 Oe for two cylindrical layered com-posites connected in the (a) series and (b) parallel modes.

equal. Considering the combined ME composite structure as an equivalent circuit, it is obvious that the V from series circuit is larger than that from parallel circuit. Thus, the maximum ME voltage coefficient of the combined ME composite structure in the parallel mode is smaller than that of the combined ME composite structure in the series mode.

Figure 4 shows the ME voltage coefficient E,V depend-ences on ac magnetic field frequency f at Hdc=150 Oe for three cylindrical layered composites connected in the series mode. The average cylinder diameters D of the three cylin-drical layered composites are 22.5, 28.5 and 34.5 mm, re-spectively. There are three resonance peaks for 1<f<150 kHz. The resonance peaks at 30.0, 35.7, 46.0 kHz are ascribed to the corresponding cylindrical layered composites with var-ious D. The results indicate that one can realize mul-ti-resonance frequencies by increasing the number of cylin-drical layered composites connected in the series or parallel mode.

Figure 5 shows the ME voltage coefficient E,V depend-ences on bias magnetic field Hdc at f=1 kHz for the com-bined ME composite structure consisting of one, two and three cylindrical layered composites. At the non-resonance frequency, the ME voltage coefficient increases as the number of cylindrical layered composites increases, indi-cating that the combined ME composite structure with more cylindrical layered composites will obtain a larger ME effect.

As the bias and ac magnetic fields are applied parallel (axial mode) to the cylinder axis direction, the ME voltage

Bi K, et al. Sci China Tech Sci October (2013) Vol.56 No.10 2575

Figure 4 Magnetoelectric voltage coefficient E,V dependences on ac magnetic field frequency f at Hdc=150 Oe for three cylindrical layered composites connected in the series mode.

Figure 5 Magnetoelectric voltage coefficient E,V dependences on bias magnetic field Hdc at f=1 kHz for the combined ME composite structure in series mode.

coefficient at the resonance frequency will increase linearly even though Hdc>8 kOe due to the piezoinductive effect of Ni/PZT/Ni cylindrical layered composites [22–24]. Hence, by using the combined composite structure, one can not only achieve multi-resonance frequencies but also obtain mul-ti-giant ME voltage coefficients at resonance frequencies.

4 Conclusions

The combined ME composite structure with multi-resonance frequencies have been made of several cylindrical layered composites connected in a series or parallel mode. Each resonance frequency is ascribed to the corresponding cylin-drical layered composites with a certain cylinder diameter. The ME voltage coefficient of the combined ME composite structure in the series mode is larger than that of the com-bined ME composite structure in a parallel mode. One can control when and how many resonance frequencies appear by changing the average cylinder diameter and the number of cylindrical layered composites connected in the series or parallel mode. The multi-resonance frequencies behavior offers the possibility of making multifunctional devices which could be used for multi-frequencies operation.

This work was supported by the National High Technology Research and Development Program of China (Grant No. 2012AA030403), National Natural Science Foundation of China (Grant Nos. 51032003, 11274198, 51102148, 51221291), Shandong Natural Science Foundation (Grant No. ZR2010AM025), the China Postdoctoral Research Foundation (Grant No. 2013M530042), and the Research Fund for the Doctoral Program of Higher Education (Grant No. 2010000612003).

1 Landau L D, Lifshitz E M. Electrodynamics of Continuous Media. Oxford: Pergamon Press, 1960. 417–418

2 Eerenstein W, Mathur N D, Scott J F. Multiferroic and magnetoelec-tric materials. Nature, 2006, 442: 759–765

3 Nan C W, Bichurin M I, Dong S X, et al. Multiferroic magnetoelec-tric composites: Historical perspective, status, and future directions. J Appl Phys, 2008, 103: 031101

4 Folen V J, Rado G T, Stalder E W. Anisotropy of the magnetoelectric effect in Cr2O3. Phys Rev Lett, 1961, 6: 607–608

5 Fetisov Y K, Bush A A, Kamentsev K E, et al. Ferrite-piezoelectric mul-tilayers for magnetic field sensors. IEEE Sens J, 2006, 6(4): 935–938

6 Fiebig M. Revival of the magnetoelectric effect. J Phys D Appl Phys, 2005, 38: R123–R152

7 Duc N, Giang D. Magnetic sensors based on piezoelectric–magneto- strictive composites. J Alloys Compd, 2008, 449: 214–218

8 Israel C, Mathur N D, Scott J F. A one-cent room-temperature mag-netoelectric sensor. Nature Mater, 2008, 7: 93–94

9 Bichurin M I, Petrov V M, Petrov R V, et al. Magnetoelectric sensor of magnetic field. Ferroelectrics, 2002, 280: 365–368

10 Bi K, Wang Y G, Pan D A, et al. Large magnetoelectric effect in mechanically mediated structure of TbFe2, Pb(Zr,Ti)O3, and non-magnetic flakes. Appl Phys Lett, 2011, 98: 133504

11 Zhang C L, Chen W Q. A wideband magnetic energy harvester. Appl Phys Lett, 2010, 96: 123507

12 Nan C W. Magnetoelectric effect in composites of piezoelectric and piezomagnetic phases. Phys Rev B, 1994, 50: 6082–6088

13 Pan D A, Bai Y, Chu W Y, et al. Ni–PZT–Ni trilayered magnetoelec-tric composites synthesized by electro-deposition. J Phys Condens Matter 2008, 20: 025203

14 Dong S X, Zhai J Y, Xing Z P, et al. Giant magnetoelectric effect (under a dc magnetic bias of 2 Oe) in laminate composites of FeBSiC alloy ribbons and Pb(Zn1/3, Nb2/3)O3-7%PbTiO3 fibers. Appl Phys Lett, 2007, 91: 022915

15 Ryu J, Carazo A V, Uchino K, et al. Magnetoelectric properties in piezoelectric and magnetostrictive laminate composites. Jpn J Appl Phys, 2001, 40: 4948–4951

16 Srinivasan G. Magnetoelectric composites. Annu Rev Mater Res, 2010, 40: 153–178

17 Bichurin M I, Filippov D A, Petrov V M, et al. Resonance magneto-electric effects in layered magnetostrictive-piezoelectric composites. Phys Rev B, 2003, 68: 132408

18 Bi K, Wang Y G, Wu W. Tunable resonance frequency of magnetoe-lectric layered composites. Sensor Actuat A-Phys, 2011, 166: 48–51

19 Chashin D V, Fetisov Y K, Tafintseva E V, et al. Magnetoelectric ef-fects in layered samples of lead zirconium titanate and nickel films. Solid State Commun, 2008, 148: 55–58

20 Pan D A, Bai Y, Volinsky A A, et al. Giant magnetoelectric effect in Ni–lead zirconium titanate cylindrical structure. Appl Phys Lett, 2008, 92: 052904

21 Jia Y M, Luo H S, Zhao X Y, et al. Giant magnetoelectric response from a piezoelectric/magnetostrictive laminated composite combined with a piezoelectric transformer. Adv Mater, 2008, 20: 4776–4779

22 Bi K, Wu W, Gu Q L, et al. Large magnetoelectric effect and reso-nance frequency controllable characteristics in Ni–lead zirconium ti-tanate–Ni cylindrical layered composites. J Alloys Compd, 2011, 509: 5163–5166

23 Fetisov Y K, Chashin D V. Transformation of alternating magnetic and electric fields in a ferroelectric-conductor ring structure. Tech Phys Lett, 2009, 35: 710–712

24 Fetisov Y K, Chashin D V, Srinivasan G. Piezoinductive effects in a piezoelectric ring with metal electrodes. J Appl Phys, 2009, 106: 044103