Microwave Magneto-Electric Interactions in Multiferroics
- PDF / 272,197 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 0 Downloads / 153 Views
0966-T14-01
Microwave Magneto-Electric Interactions in Multiferroics Gopalan Srinivasan1, A.S. Tatarenko1, Y. K. Fetisov1, V. Gheevarughese1, and M.I. Bichurin2 1 Physics, Oakland University, Rochester, MI, 48309 2 Institute for Electronic and Information Systems, Novgorod State University, Novgorod, Russian Federation
ABSTRACT Investigations on microwave magneto-electric (ME) interactions at 1-10 GHz have been carried out on yttrium iron garnet (YIG)-lead zirconate titanate (PZT) and YIG-lead magnesium niobate lead titanate (PMN-PT) bilayers. Ferromagnetic resonance is a powerful tool for such studies. An electric field E applied to the composite produces a mechanical deformation in PZT or PMN-PT, resulting in a shift in the resonance field for YIG. Information on the nature of high frequency ME coupling has been obtained from data on resonance field shift vs E. A cavity resonator or stripline structure was used. The measured ME interactions are in the range 1-5 Oe cm/kV. The coupling strength has been found to be dependent on magnetic field orientation. The strongest interaction is measured in YIG-PZT systems. The design and characterization of ferromagnetic resonance based, electric field tunable ME resonators and filters are discussed.
INTRODUCTION The electromagnetic coupling in a ferromagnetic-ferroelectric heterostructure is facilitated by mechanical deformation [1]. In an applied magnetic field, for example, deformation arises due to magnetostriction and results in an induced polarization because of piezoelectric effect. Investigations so far have mainly focused on low frequency (10 Hz – 500 kHz) magnetoelectric (ME) phenomena [2-4]. Ferromagnetic resonance (FMR) is a powerful tool for studies on microwave ME effects in ferrite-PZT. An electric field E applied to the composite produces a mechanical deformation in PZT that in turn is coupled to the ferrite, resulting in a shift δHE in the resonance field. Information on the nature of high frequency ME coupling could therefore be obtained from data on shift δHE vs E [5,6]. We proposed a model for the general response of a layered or bulk composite to microwave fields in the presence of dc fields E and H [7,8]. There are two important interactions, (i) coupling between microwave magnetic field and E and (ii) between microwave magnetic and electric fields, and are described in terms of magnetic and ME susceptibilities. Figures 1 shows the estimated E and H dependence of magnetic susceptibility χ for disks of bilayers of lithium ferrite (LFO)-lead zirconate titanate (PZT), nickel ferrite (NFO)– PZT and yttrium iron garnet (YIG)-PZT. The estimates are for E and H perpendicular to the sample plane and for ME constants in Refs. 7 and 8. For E = 0, the profiles in Fig.1 show the FMR. With the application of E = 300 kV/cm, a down-shift occurs for the resonance field Hr; its magnitude is determined by the piezoelectric and magnetoelastic constants. The shift δHE varies from a maximum of 330 Oe for NFO-PZT to a minimum of 22
Oe for YIG-PZT. The large magnetostricti
Data Loading...
