Laser Pulses Could Make Computer Memory More Than 1,000 Times Faster

Researchers at the University of California San Diego have published findings in Nature Communications showing a potential breakthrough in data storage speed. By carefully shaping and shrinking the beam of an ultrafast laser, the team demonstrated it is possible to switch the magnetic states that underpin how digital data is written to storage devices. This technique, known as optical switching, could work more than 1,000 times faster than the conventional approach used in hard drives and other storage systems today, which relies on external magnetic fields to flip the orientation of tiny magnetic regions in a recording material.

The UC San Diego team overcame two longstanding obstacles that had held the method back. Earlier experiments had only succeeded with magnetic structures containing three or fewer magnetic layers, and required light of a specific polarization. By engineering the beam's shape and size, the researchers demonstrated optical switching in a thicker structure — nine alternating layers of platinum and cobalt — without needing a particular polarization. A smaller, more precisely shaped beam also opens the door to denser storage, since it can target smaller magnetic regions.

Senior author Abdoulaye Ndao, a professor in the Department of Electrical and Computer Engineering, collaborated with thin-film magnetic materials expert Eric Fullerton, also at UC San Diego. First author Muhammad Waleed Khalid, a PhD student, noted the team spent significant effort verifying their unusual results before the broader community accepted them. Challenges remain: the specialised ultrafast lasers used are not yet easily integrated into computer chips. The team is working to shrink the beam further — targeting a few hundred nanometers — as a step toward practical, next-generation memory devices.