Spintronics

SpintronicsOur work in spintronics is currently centered on the long-range transport of spin signals in insulating magnets with a special interest in antiferromagnets. Towards this goal, we employ collective spin excitations such as magnons, domain walls, and magnetic skyrmions as spin carriers in nonlocal device geometries. For generation and detection of such collective excitations, we rely on mechanisms such as spin-orbit torque, spin pumping, and spin Seebeck effect at the interface of heavy metals (e.g., Pt) and magnetic insulators.

We are also very keen on using spin transport as a probe of quantum magnetism in correlated material systems, especially when conventional techniques fail to provide insight. This is often the case in antiferromagnets and materials with disordered magnetic states.

Antiferromagnetic Spin Switching

Antiferromagnetic Spin SwitchingData loss is a major issue in modern electronics. Charged-based devices are vulnerable to ionizing radiation while ferromagnetic-based memory devices are susceptible to data loss from external magnetic fields. However, Antiferromagnetic (AFM) based memory devices are robust to both charge and magnetic field perturbations. There exists a handful of materials whose AFM spin textures can be electrically “switched'': an applied current induces a spin polarization due to a combination of inversion symmetry and spin-orbit coupling that transfers angular momentum into the system, exerting a spin-orbit torque on the magnetic domains. This torque rotates the conductivity tensor, providing a switch between distinct resistance states.

Our lab seeks to leverage the correlated behavior of transition metal dichalcogenides (TMD) which exhibit superconductivity, magnetism, charge density waves (CDW) and Mott physics. Magnetically intercalated TMDs can possess competing AFM orders which can form a platform to build electrically switchable antiferromagnetic based devices. Analogous to the AFM domains, we also seek to explore the possibility of electrically controlling the electronic charge order reconstruction of CDWs found in pristine TMDs where in this case, the electrically switchable device would be based on the manipulation of the CDWs.