Phase Locked Loop of the Spin-Torque Nanooscillator

TL;DR

This paper investigates the dynamics of a phase locked loop in spin-torque nanooscillators, highlighting unique phase locking behavior and bifurcations affecting microwave oscillations under various conditions.

Contribution

It provides a detailed analysis of phase locking bands and bifurcations in STNOs' PLLs, revealing their distinctive phase locking characteristics compared to other microwave sources.

Findings

Identification of phase locking and synchronism bands.

Existence of a phase locking band without a filter.

Bifurcations caused by frequency detuning.

Abstract

We have studied the dynamics of a spin-torque nanooscillator's (STNO) phase locked loop (PLL) generating microwave oscillations in a broad range of frequencies under the effect of direct current and external magnetic field. Bifurcations in the system caused by a change in the frequency detuning of synchronized oscillations are considered. Bands of phase locking and synchronism are determined. The existence of a phase locking band in the filterless PLL of STNOs basically distinguishes these oscillators from other types of microwave generators.