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Time domain measurement of phase noise in a spin torque oscillator



Mark W. Keller, Anthony B. Kos, Thomas J. Silva, William H. Rippard, Matthew R. Pufall


We measure phase noise from the zero crossings of the voltage vs. time waveform of a spin torque nanocontact oscillating in a vortex mode. The power spectrum of the phase noise varies with Fourier frequency f as 1/f2, consistent with frequency fluctuations driven by a thermal source. We compare the linewidth due to phase noise with that measured using a spectrum analyzer. A phase-locked loop reduces the phase noise for frequencies within its 3 MHz bandwidth.
Applied Physics Letters


spin torque, phase noise, phase-locked loop


Keller, M. , Kos, A. , Silva, T. , Rippard, W. and Pufall, M. (2009), Time domain measurement of phase noise in a spin torque oscillator, Applied Physics Letters, [online], (Accessed June 20, 2024)


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Created May 13, 2009, Updated February 19, 2017