Wyatt Ackerman

Major: Physics

Mentors: Charles Tam, Stephen Wilson

Temperature-Dependent Magnetic Susceptibility of Iron Antimonide Telluride

Iron diantimonide, FeSb2, is a correlated narrow-gap semiconductor with unusual electronic and magnetic properties. It’s been shown that partial substitution of Sb with Te introduces additional charge carriers, resulting in the emergence of ferromagnetic characteristics at low temperatures. While previous studies have established the emergence of ferromagnetism in Te-dope FeSb2, detailed investigations of the field-dependent magnetic susceptibility and zero-field-cooled (ZFC) / field-cooled (FC) behavior remained unexplored. In this work, we investigate the magnetic susceptibility of FeSb1.8Te0.2 single crystals via SQUID magnetometry. A single crystal was thoroughly characterized prior to selection for ZFC/FC and magnetization hysteresis measurements. Magnetometry measurements reveal highly correlated temperature-dependent susceptibility at low temperatures not observed in FeSb2. The primary ferromagnetic transition is observed at a temperature of 24K. Additional unexpected anomalous magnetic transitions, such as a precursor transition around 88K, were also observed. These results provide additional supplementary characterization of the low-temperature magnetic properties of electron-doped FeSb2 and contribute to understanding the relationship between charge carrier doping and emergent magnetic order in correlated semiconducting materials.