Theory of the Magnon Parametron

TL;DR

This paper develops a theoretical framework for the magnon parametron, a ferromagnetic system driven by microwaves, revealing its dynamical phases and potential for quantum computing applications.

Contribution

It introduces a comprehensive model of the magnon parametron dynamics, including thermal and quantum effects, and identifies three distinct operational regimes.

Findings

Identification of three dynamical phases: stable Ising spin, telegraph noise, and quantum correlated regime.

Prediction of magnon entanglement at lower temperatures.

Potential for alternative computing schemes using the magnon parametron.

Abstract

The 'magnon parametron' is a ferromagnetic particle that is parametrically excited by microwaves in a cavity. Above a certain threshold of the microwave power, a bistable steady state emerges that forms an effective Ising spin. We calculate the dynamics of the magnon parametron as a function of microwave power, applied magnetic field and temperature for the interacting magnon system, taking into account thermal and quantum fluctuations. We predict three dynamical phases, viz. a stable Ising spin, telegraph noise of thermally activated switching, and an intermediate regime that at lower temperatures is quantum correlated with significant distillible magnon entanglement. These three regimes of operation are attractive for alternative computing schemes.