Orbital magnets without spin magnetization for orbitronics

Theoretical predictions and recent experimental observations of electron orbital angular momentum dynamics draw growing interest in orbitronics. A representative application of the orbital current is the orbital torque. However, the present setup for the orbital torque utilizes the orbital-to-spin conversion in ferromagnets, which lowers the torque efficiency. This motivates one to search for orbital magnets, whose net magnetization originates primarily from orbital magnetic moments. When conventional spin magnets in the present orbital torque setup are replaced by orbital magnets, the orbital-to-spin conversion process may be bypassed, opening a path to enhance the torque efficiency. Here, we propose a design strategy for orbital magnets. We demonstrate the strategy for double perovskites via first-principles calculations and identify seven promising candidate materials for orbital magnets.