PHYSICS: How to Create a Spin Current

Conventional electronics devices use the electron charge to carry information. In contrast, the emerging field of spintronics relies on the electron spin. Advanced spintronics devices will require the generation and manipulation of a spin current, but present methods for achieving such a current are cumbersome and inefficient, requiring the use of external magnetic fields and ferromagnets. In his Perspective, Sharma reviews a method for generating spin currents that can overcome these obstacles. This method of pumping spins involves electrically modulating the path of electrons in semiconductor materials. It allows for the manipulation of both the direction of the current and the direction of its spin polarization.