  Spin transfer torques allow for electrical manipulation of magnetization at
room temperature, which is utilized to build future electronic devices such as
spin transfer torque memories. Recent experiments have discovered that the
combination of the spin transfer torque with the spin Hall effect enables more
efficient manipulation. A versatile control mechanism of such spin-orbit
torques is beneficial to envision device applications with competitive
advantages over the existing schemes. Here we report that the oxidation
manipulation of spin-orbit torque devices triggers a new mechanism, and the
resulting torques are estimated to be about two times stronger than that of the
spin Hall effect. Our result introduces an entirely new way to engineer the
spin-orbit torques for device operation via oxygen manipulation. Combined with
electrical gating for the control of the oxygen content, our finding may also
pave the way for towards reconfigurable logic devices.
