The Storage Revolutionary

In the late 1980s, Peter Grünberg was investigating nanometer-thick layers of iron and chromium at Forschungszentrum Jülich. In the process, he discovered an exceptionally strong physical effect: the electrical resistance of such layered systems changes dramatically when their magnetic alignment changes. The effect was significantly stronger than previously known magnetoresistive phenomena—hence the name giant magnetoresistance (GMR).

What began as basic research turned out to be a technological breakthrough. GMR enables the detection of extremely small magnetic changes with high precision. In the 1990s, manufacturers began using this capability in the read heads of modern hard drives. The effect enabled a dramatic increase in storage capacity and made high-density data storage economically viable.

The impact is global: billions of hard drives worldwide rely on GMR technology. Without this development, compact laptops, smartphones, and modern data centers in their current form would be virtually unthinkable.

For his discovery, Peter Grünberg was awarded the Nobel Prize in Physics in 2007, jointly with Albert Fert. GMR is considered a foundational technology in spintronics, a field of research that utilizes electron spin for memory and sensor applications. What began as an experiment with atomically thin layers became a key technology of the digital world—an example of how Helmholtz research transforms knowledge into societal impact.

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