Evidence for linear dependence of exchange bias on pinned uncompensated spins in an Fe/FeO bilayer

We use a magnetic field to manipulate the pinned spins in an Fe/FeO bilayer at room temperature, observing the behavior of the pinned magnetic moment via magnetometry. Our experiment reveals a linear relationship between the exchange bias field and the pinned magnetic moment. Based on the pinned uncompensated spin density at the interface as a function of the pinned moment, we provide a quantitative description of the exchange bias effect via exchange interaction of ferromagnetic and antiferromagnetic spins.