# Matter-wave interferometry using a levitated magnetic nanoparticle

## TL;DR

This paper demonstrates matter-wave interferometry with a 20 nm ferromagnetic nanoparticle, creating a mesoscopic Schrödinger cat state with a large spatial separation, advancing quantum superposition experiments.

## Contribution

It introduces a novel all-optical spin polarization technique enabling matter-wave interferometry with a levitated ferromagnetic nanoparticle, achieving unprecedented spatial separation.

## Key findings

- Creation of a mesoscopic Schrödinger cat state.
- Maximum spatial separation of 25 micrometers.
- Use of a 20 nm ferromagnetic nanoparticle in quantum superposition.

## Abstract

The superposition principle is one of the bizarre predictions of quantum mechanics. Nevertheless, it has been experimentally verified using electrons, photons, atoms, and molecules. In this article, using a $20~$nm levitated ferromagnetic FePt nanoparticle, an exotic all optical spin polarization technique and the matter-wave interferometry, we show that a mesoscopic spatial Schrodinger cat can be created. Additionally, we argue that the maximum spatial separation between the delocalized wavepackets can be $25~\mu m$ and is significantly larger than the object itself.