Modulation of anomalous Hall angle in a magnetic topological semimetal

Abstract

The anomalous Hall angle (θA) is a measure of the efficiency of converting a longitudinal driving current to a transverse spin-polarized Hall current. For anomalous Hall sensing, a large anomalous Hall angle can improve the sensitivity of magnetic field detection. However, modulation of this angle is challenging and magnetic materials typically have low angles of 0.1 to 3°. Here, we report modulation of the anomalous Hall angle in the magnetic Weyl semimetal Co3Sn2S2. We propose that the angle parameter tanθA can be formulated as a function of the product of electrical resistivity and anomalous Hall conductivity. Our scheme was utilized to demonstrate the modulation of tanθA up to a magnitude of 0.46, corresponding to an angle of around 25°. Microfabricated anomalous Hall devices using Fe-doped Co3Sn2S2 single-crystalline nanoflakes exhibit a high Hall sensitivity of 7028 μΩucm/T and a magnetic field detectability of 23.5 nT/Hz0.5 at 1 Hz.