Work

Ultrafast switching of antiferromagnetic order by field-derivative torque

Year: 2026

Type: article

Abstract: Control of magnetic order in antiferromagnets is a central challenge in the development of next-generation spintronic devices. Here, we propose and analyze magnetization switching driven by the field-derivative torque, a torque that originates from the time-derivative of an applied THz pulse acting on the staggered order parameter. Using atomistic spin simulations, we show that the field-derivative torque couples efficiently to the Néel vector, enabling deterministic switching without net spin accumulation. Further, we show that using the circularly polarised THz pulse, the FDT-induced magnetization switching reduces the required THz magnetic field by two-fold. To this end, we compute the switching and non-switching areas as a function of THz pulse width, THz magnetic field, and damping of the antiferromagnetic material. We find that the switching and non-switching areas are completely deterministic in antiferromagnets. Moreover, the switching area increases by about 55% when the FDT is considered.

Source: Physical review. B./Physical review. B

DOI: 10.1103/x9m5-yp3c

Authors: Pratyay Mukherjee, Ritwik Mondal

Institution: Indian Institute of Technology Dhanbad

Language: English

Topic: Magnetic properties of thin films

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Indian Institute of Technology (Indian School of Mines), Dhanbad, Science and Engineering Research Board

Awards: G5309673647, G8947093378