1. Influence of frequency and DC bias on magneto-impedance behaviors in double-MgO magnetic tunnel junctions
- Author
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Kuo, K.M., Lin, C.Y., Lin, C.T., Chern, G., Chao, C.T., Horng, Lance, Wu, J.C., Wu, Teho, Huang, C.Y., Ohyama, H., Isogami, S., Tsunoda, M., and Takahashi, M.
- Subjects
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MAGNESIUM compounds , *ELECTRIC impedance , *MAGNETIZATION , *MAGNETORESISTANCE , *PHASE diagrams , *ELECTRIC potential , *DIRECT currents - Abstract
Abstract: Magneto-impedance (MI) of a double-barrier MgO magnetic tunnel junction (DMTJ) is measured as a function of frequency (20 Hz–3 MHz) and DC bias (−1 to 1 V) under magnetic parallel and antiparallel states. A strong nonlinear effect is observed at all frequencies and the MI changes from positive to negative at the relaxation frequency ∼1/RC. A frequency–dc bias () “phase diagram” is mapped out to describe the combination effects of the magneto-impedance response. The decay of the tunnel magneto-resistance (TMR) and tunnel magneto-capacitance (TMC) at high voltage is sufficiently reduced by the double-MgO barrier. The V1 / 2 (the voltage that magnetic response drops to 1/2 of its maximum) of TMC reaches an average value of ∼1.35 V, which is larger than the V1 / 2 of TMR ∼0.95 V, suggesting that the response of TMC is more stable than TMR for high frequency application. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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