Quantum information diode based on a magnonic crystal

TL;DR

This paper proposes a quantum information diode utilizing nonreciprocal magnons in a magnonic crystal, allowing controlled asymmetric quantum information transport via external electric fields, with potential fabrication from YIG films.

Contribution

It introduces a novel quantum information diode concept based on nonreciprocal magnons and magnonic crystals, with controllable rectification using electric fields and feasible experimental implementation.

Findings

Magnons exhibit nonreciprocal propagation in a magnonic crystal.

External electric fields can control quantum information rectification.

The device can be fabricated from yttrium iron garnet (YIG) films.

Abstract

Exploiting the effect of nonreciprocal magnons in a system with no inversion symmetry, we propose a concept of a quantum information diode, {\it i.e.}, a device rectifying the amount of quantum information transmitted in the opposite directions. We control the asymmetric left and right quantum information currents through an applied external electric field and quantify it through the left and right out-of-time-ordered correlation (OTOC). To enhance the efficiency of the quantum information diode, we utilize a magnonic crystal. We excite magnons of different frequencies and let them propagate in opposite directions. Nonreciprocal magnons propagating in opposite directions have different dispersion relations. Magnons propagating in one direction match resonant conditions and scatter on gate magnons. Therefore, magnon flux in one direction is damped in the magnonic crystal leading to an asymmetric transport of quantum information in the quantum information diode. A quantum information diode can be fabricated from an yttrium iron garnet (YIG) film. This is an experimentally feasible concept and implies certain conditions: low temperature and small deviation from the equilibrium to exclude effects of phonons and magnon interactions. We show that rectification of the flaw of quantum information can be controlled efficiently by an external electric field and magnetoelectric effects.