Efficient all-optical helicity dependent switching of spins in a Pt/Co/Pt film by a dual-pulse excitation

TL;DR

This paper demonstrates a dual-pulse laser technique to achieve efficient all-optical helicity dependent switching of spins in a Pt/Co/Pt film, significantly reducing the number of pulses needed for magnetization reversal.

Contribution

It introduces a dual-pulse excitation method that reduces the required laser pulses for AO-HDS in ferromagnetic metals, enhancing efficiency.

Findings

Magnetization reversal achieved with only 4 pulse pairs.

Dual-pulse approach reduces energy and time for switching.

Potential for practical applications in spintronics.

Abstract

All-optical helicity dependent switching (AO-HDS), deterministic control of magnetization by circularly polarized laser pulses, allows to efficiently manipulate spins without the need of a magnetic field. However, AO-HDS in ferromagnetic metals so far requires many laser pulses for fully switching their magnetic states. Using a combination of a short, 90-fs linearly polarized pulse and a subsequent longer, 3-ps circularly polarized pulse, we demonstrate that the number of pulses for full magnetization reversal can be reduced to 4 pulse pairs in a single stack of Pt/Co/Pt. The obtained results suggest that the dual-pulse approach is a potential route towards realizing efficient AO-HDS in ferromagnetic metals.