My name is Lauren, and I am a postdoctoral fellow in the Laboratory for Mesoscopic Systems at the Department of Materials at ETH Zurich. Our research focuses on magnetic materials – systems that underpin many technologies we rely on in our daily lives. These span from computers to sensors and radio-frequency electronics. One of our lab’s central missions is to develop new magnetic materials and architectures for more efficient data storage and processing, which is what attracted me here back in 2022.

Before I joined, a former lab member, Zhaochu Luo, developed a remarkable method to pattern magnetic anisotropy—that is, to control the direction of the magnetization. Traditionally, the magnetization aligns along a single axis (for example, south-north), but his work demonstrated that it could also be engineered on the same surface along an orthogonal direction (for example, east-west). Beyond the fundamental interest, this opened the door to storing and processing information in the same physical location – an approach that could significantly reduce energy consumption and accelerate computation. The work sparked significant excitement in the community and led to a patent.

At the heart of this breakthrough was a clever material trick: selectively oxidizing the surface of the material using through a lithographic mask. With this trick, we realized that, with this single material change, one can achieve fascinating things. However, while very impactful, this method is limited to a relatively small class of materials, which are largely outside of the technologically relevant materials. When I arrived in Zurich, my goal was to expand this concept to a broader range of systems, particularly for applications in magnonics, a field that uses spin waves to carry and process information, offering a potential low-energy alternative to conventional electronics.

I had a clear vision, supported by an ETH fellowship—but one critical question remained: How could we pattern magnetic properties without relying only on oxidation?

The answer emerged unexpectedly. After weeks of thinking about this question, I gathered my colleagues in our meeting room to brainstorm. During that discussion, a simple but unconventional idea surfaced: What if we used our direct laser writer—not for lithography, as intended—but to locally heat the material? It sounded pretty crazy. The tool was designed to pattern light sensitive resists for further lithography processes, not to locally heat materials. Yet the tool allows precise control of laser power, and therefore of the heat induced in the material.

Curious, we decided to give it a go. Within days, together with my colleague Jeff, we tested the idea on different materials we had prepared so far. To our surprise, it simply worked. Instead of heating entire samples in an oven for hours to anneal them, we could now modify properties on nanometer length scales and on nanosecond timescales. Over the following months, we expanded this approach to new material systems and even developed grayscale patterning, where magnetic properties vary continuously across the surface and in complex patterns. This opens up new possibilities for device design and could be readily adopted by other researchers using similar tools. Looking back, what stands out is not just what we achieved, but the process we went through to get to the final result. Our progress came from open discussions, from being willing to challenge conventional wisdom, and from exploring simple ideas in unusual ways. Stepping outside one’s comfort zone and engaging with others can be just as important as having technical expertise. And often the most effective solutions are not the most complex ones, but rather the simplest ones, seen from a different perspective.