Electromagnetic propulsion and separation by chirality of nanoparticles in liquids

TL;DR

This paper presents a novel electromagnetic method for propelling and separating chiral nanoparticles in liquids using uniform magnetic and alternating electric fields, with potential technological applications.

Contribution

It introduces a new mechanism leveraging magnetic and electric fields to control and separate chiral nanoparticles based on their chirality.

Findings

Opposite chiral isomers move in opposite directions under the fields.

The chiral velocity component depends on the particle's angular momentum.

The mechanism mimics gyroscopic response of ferromagnetic particles.

Abstract

We introduce a new mechanism for the propulsion and separation by chirality of small ferromagnetic particles suspended in a liquid. Under the action of a uniform d.c. magnetic field H and an a.c. electric field E isomers with opposite chirality move in opposite directions. Such a mechanism could have a significant impact on a wide range of emerging technologies. The component of the chiral velocity that is odd in H is found to be proportional to the intrinsic orbital and spin angular momentum of the magnetized electrons. This effect arises because a ferromagnetic particle responds to the applied torque as a small gyroscope.