Ultra-sensitive anomalous Hall effect sensors based on Cr-doped Bi2Te3topological insulator thin films

The observation of anomalous Hall effect (AHE) in magnetically doped topological insulators brings a new candidate of Hall sensor with low power consumption. In this work, the transport properties and the sensitivity of AHE sensors based on Cr-doped Bi(2)Te(3)thin films were studied. Obvious AHEs induced by ferromagnetic ordering were presented in all Cr(x)Bi(2-x)Te(3)sensors. At the optimized doping concentration ofx= 0.09, a high sensitivity of 6625 omega T(-1)was achieved, which has increased by 2.5 times compared to the highest reported one in Cr-doped Bi2Te3. More importantly, a considerable sensitivity of 4082 omega T(-1)can be obtained up to 20 K, which implies a higher working temperature than other reports. Our findings suggest Cr-doped Bi(2)Te(3)sensor could be a good candidate for highly sensitive AHE sensors and reveal the extraordinary potential of magnetic TIs in the applications of field detection.