Scientists have discovered semi-Dirac fermions—quasiparticles that exhibit massless behavior in one direction and massive behavior in another—within crystals of ZrSiS, a semi-metal. This finding, published in Physical Review X, was achieved through magneto-optical spectroscopy, a technique involving infrared light and strong magnetic fields. Lead author Yinming Shao from Penn State stated that the observation was unexpected, as they initially aimed to study different properties of ZrSiS. The quasiparticles were theorized 16 years ago, but this marked their first experimental identification.
When subjected to a strong magnetic field, the behavior of electrons in ZrSiS deviated from expected norms, revealing a distinctive transition pattern aligned with the theoretical predictions for semi-Dirac fermions. This unique mass-changing property could lead to significant technological advancements in areas such as batteries and sensors. The layered structure of ZrSiS resembles that of graphene, indicating potential for applications in emerging technologies. Ongoing research aims to unravel the remaining mysteries surrounding these quasiparticles, as their properties continue to challenge existing theoretical frameworks in quantum physics.
