Dr. Atul Pandey sucessfully defended his thesis - congratulations!

Atul worked on an “Opto-electrical approach to visualize magnetic nanostructures of chiral antiferromagnets”

Title: “Opto-electrical approach to visualize magnetic nanostructures of chiral antiferromagnets”

Modern data storage devices like USB sticks and hard drives rely on nanoscale-sized magnets. Here, the binary data is encoded into the magnetic states of such tiny magnets. Reading and writing data from memory devices requires detecting and manipulating the magnetic states of nanoscale magnets. In this regard, chiral noncollinear antiferromagnets are promising candidates for future-generation memory devices that are compact and faster.

Atul’s PhD work investigates magnetization switching in a Mn₃Sn based noncollinear antiferromagnet at the nanoscale. A new magnetic domain imaging technique based on optical near-field was used for this. It was found that illuminating a sharp metallic tip with a laser beam creates a temperature gradient confined to fifty nanometers. This gradient generates an electrical signal due to the Anomalous Nernst effect. Measuring this signal enabled the detection of the magnetic state of Mn₃Sn magnetic domains as small as fifty nanometers.