Spin torque nano-oscillators with a perpendicular spin polarizer<xref rid="cpb_28_3_037503fn1" ref-type="fn">*</xref><fn id="cpb_28_3_037503fn1"><label>*</label><p>Project supported by the National Basic Research Program of China (Grant No. 2015CB921501) and the National Natural Science Foundation of China (Grant Nos. 11774260, 51671057, and 11874120).</p></fn>

Spin torque nano-oscillators with a perpendicular spin polarizer**

Project supported by the National Basic Research Program of China (Grant No. 2015CB921501) and the National Natural Science Foundation of China (Grant Nos. 11774260, 51671057, and 11874120).

Zheng Cuixiu¹, Chen Hao-Hsau², Zhang Xiangli², Zhang Zongzhi², Liu Yaowen^{1, †}

(a)–(c) Digital FSK modulation based on PERP-STNO operated by current pulse only. (a) Magnetization precession trajectories at two current pulses of I₀ = 0.1 mA and I₁ = 2 mA, respectively. The pulse duration is 10 ns. (b) Frequency spectra of the two precession states calculated by FFT transformation. (c) The evolution of x-component of magnetization. (d)–(f) Digital FSK modulation implemented through the collaborative operation between the current and field pulses. The magnetization precessions are forced into the orbit with m_z = 0. (d) Magnetization precession trajectories at (I₁, h_z1) and (I₂, h_z2), corresponding to the bits “0” and “1”, respectively. (e) The frequency spectra of the two precession states. (f) The time evolution of m_x and m_z response to the current and field pulses.