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Critical current under an optimal time-dependent polarization direction for Stoner particles in spin-transfer torque induced fast magnetization reversal

Z. Z. Sun·X. R. Wang
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Abstract

Fast magnetization reversal of uniaxial Stoner particles by spin-transfer torque due to the spin-polarized electric current is investigated. It is found that a current with a properly designed time-dependent polarization direction can dramatically reduce the critical current density required to reverse a magnetization. Under the condition that the magnitude and the polarization degree of the current do not vary with time, the shape of the optimal time-dependent polarization direction is obtained such that the magnetization reversal is the fastest.

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Z. Z. Sun, X. R. Wang. 2006-08-25. Critical current under an optimal time-dependent polarization direction for Stoner particles in spin-transfer torque induced fast magnetization reversal. https://doi.org/10.1103/physrevlett.98.077201

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