Classical analog of qubit logic based on a magnon Bose-Einstein condensate

TL;DR

This paper demonstrates a classical analog of qubit operations using a two-component magnon Bose-Einstein condensate in a magnetic film, enabling initialization and manipulation similar to quantum bits at room temperature.

Contribution

It introduces a classical system that mimics qubit functionalities using magnon BECs, including initialization and control methods.

Findings

Successful initialization of the classical qubit states.

Demonstration of Rabi-oscillation analogs in wavevector space.

Potential for room-temperature classical quantum information processing.

Abstract

We present a classical version of several quantum bit (qubit) functionalities using a two-component magnon Bose-Einstein condensate formed at opposite wavevectors in a room-temperature yttrium-iron-garnet ferrimagnetic film. The macroscopic wavefunctions of these two condensates serve as orthonormal basis states that form a system being a classical counterpart of a single qubit. Solving the Gross-Pitaevskii equation and employing micromagnetic numerical simulations, we first show how to initialize the system in one of the basis states: the application of wavevector-selective parallel parametric pumping allows us to form only a single condensate in one of the two lowest energy states of the magnon gas. Next, by translating the concept of Rabi-oscillations into the wavevector domain, we demonstrate how to manipulate the magnon-BEC system along the polar axis in the Bloch sphere representation. We also discuss the manipulation regarding the azimuthal angle.