Strongly nonlinear antiferromagnetic dynamics in high magnetic fields

TL;DR

This paper demonstrates the use of THz light and high magnetic fields to induce and control highly nonlinear antiferromagnetic dynamics in NiO, advancing ultrafast magnetic switching capabilities.

Contribution

It introduces a method to drive and steer antiferromagnetic NiO into and out of nonlinear regimes using THz light and strong magnetic fields, a largely unexplored area.

Findings

Achieved large-amplitude nonlinear AFM dynamics in NiO.

Controlled nonlinearity with a 33-Tesla magnetic field.

Paved the way for ultrafast resonant switching of AFM order.

Abstract

Antiferromagnetic (AFM) materials possess a well-recognized potential for ultrafast data processing thanks to their intrinsic ultrafast spin dynamics, absence of stray fields, and large spin transport effects. The very same properties, however, make their manipulation difficult, requiring frequencies in THz range and magnetic fields of tens of Teslas. Switching of AFM order implies going into the nonlinear regime, a largely unexplored territory. Here we use THz light from a free electron laser to drive antiferromagnetic NiO into a highly nonlinear regime and steer it out of nonlinearity with magnetic field from a 33-Tesla Bitter magnet. This demonstration of large-amplitude dynamics represents a crucial step towards ultrafast resonant switching of AFM order.