IISc Develops Smart Magnetic Materials with Reversible Spin-State Switching for Sensors and Quantum Applications

Researchers at the Indian Institute of Science (IISc) have synthesized novel chemical frameworks capable of reversible magnetic switching triggered by external stimuli.

Abhishek Mondal, Associate Professor at the Solid State and Structural Chemistry Unit (SSCU), and his team created highly porous crystals from self-assembling metal-organic layers. These materials can change their magnetic state in response to light, heat, or mechanical pressure. The work appears in two studies published in "Angewandte Chemie" and "Small".

The first study addresses magnetic switching in 3D beehive-type porous materials used for gas or liquid sensing. In these frameworks, gas or liquid molecules entering or leaving the structure cause the crystal lattice to expand or contract, influencing atomic spin states. The team designed a highly porous complex with an elastic matrix that enables cooperative behaviour: when one atom switches spin states, the effect propagates through the lattice, causing the entire material to switch magnetic states. This transition is fully reversible and can also be triggered by light and heat.

Krishna Kaushik, PhD student at SSCU and first author of both studies, noted the focus on achieving transitions near ambient temperatures. Many ...