Ultra-fast GHz-range swept-tuned spectrum analyzer with 20 ns temporal resolution based on a spin-torque nano-oscillator with a uniformly magnetized 'free' layer

TL;DR

This paper presents a GHz-range swept-tuned spectrum analyzer using a spin-torque nano-oscillator with 20 ns temporal resolution, enabling ultra-fast, wide-band, time-resolved spectral analysis limited only by the bandwidth theorem.

Contribution

The work introduces a novel spectrum analyzer based on a uniform-state spin-torque nano-oscillator capable of nanosecond time-scale spectral analysis in the GHz range.

Findings

Achieved 20 ns temporal resolution in GHz-range spectral analysis.

Demonstrated effective spectral analysis of rapidly varying signals.

Utilized a spin-torque nano-oscillator with a uniform free layer for wide-band analysis.

Abstract

The advantage of an ultra-fast frequency-tunability of spin-torque nano-oscillators (STNOs) that have large (> 100MHz) relaxation frequency of amplitude fluctuations is exploited to realize ultra-fast wide-band time-resolved spectral analysis at nanosecond time scale with the frequency resolution limited only by the 'bandwidth' theorem. The demonstration is performed with an STNO generating in the 9 GHz frequency range, and comprised of a perpendicular polarizer and a perpendicularly and uniformly magnetized 'free' layer. It is shown that such a uniform-state STNO-based spectrum analyzer can efficiently perform spectral analysis of frequency-agile signals with rapidly varying frequency components.