Modic Group

Thermodynamics of quantum materials at the microscale

Modern quantum materials, such as unconventional superconductors, quantum spin liquids, and topological semimetals, host a wide variety of emergent states of matter. A grand experimental challenge is to determine the broken symmetries and topological structure of these states. The Modic group combines custom-built thermodynamic probes with state-of-the-art sample preparation to answer these questions.

The group uses advanced focused-ion beam (FIB) micro-structuring to design unique experiments and broaden the search space for discovery. For example, topological materials are expected to produce the next generation of electronics, but their surface-state properties are usually inaccessible to bulk measurements, such as resistivity or magnetization. Using the FIB, they can increase the surface-to-volume ratio of the sample and detect surface states directly. Modic and her team primarily develop two powerful thermodynamic and symmetry-sensitive techniques for use at the microscale: resonant torsion magnetometry and pulsed-echo ultrasound. At ISTA, they also have the in-house capability to perform electrical transport, heat capacity and magnetization at low temperatures (300 mK) and at moderate magnetic fields (14 tesla). Magnetic fields are a versatile tuning parameter that can be used to drive materials into new states of matter, to map Fermi surface geometries, and to measure the strength of magnetic interactions. The group has expertise in designing experiments that work in pulsed magnetic fields up to 100 tesla, and the scientists regularly travel to high-field facilities around the world.