Speaker
Description
Magnetic Weyl semimetals are an exciting class of quantum materials where topology and magnetism come together in the same system. This combination makes them especially important for exploring Berry-curvature-driven transport, optical responses, and unconventional magnetic phases. Recently, the RAlSi/RAlGe family, where R represents a rare-earth metal, has received growing attention because of its unusual magnetic, electronic, transport, and optical behavior. Among these materials, GdAlSi is particularly interesting because ARPES measurements and density functional theory suggest that it hosts Weyl electronic states together with an unconventional magnetic phase known as altermagnetism. In an altermagnet, the net magnetization is nearly zero, similar to an antiferromagnet, but time-reversal symmetry is still broken, and the electronic bands can show momentum-dependent spin splitting, similar to a ferromagnet. This makes GdAlSi a unique material for studying how magnetic symmetry, Weyl topology, and light-matter interaction are connected.
While several transport studies have already provided valuable information about GdAlSi, its optical and optoelectronic responses are still not well explored. In this work, we study the photothermal and photoresponse behavior of GdAlSi. The photothermal measurements are used to track magnetic phase transitions, while the photoresponse measurements are used to search for possible chirality-dependent signatures related to its Weyl electronic structure. Through these measurements, our goal is to provide a clearer experimental picture of how altermagnetism, Weyl topology, and optical response interact in GdAlSi.
