Magnetoresistance Amplification Effect in Silicon Transistor Device

Large magnetoresistance discovered in nonmagnetic semiconductors offers an alternative route to renew magnetoelectronics without ferromagnets. However, it is still a great challenge to retain such large magnetoresistance under low magnetic fields. In this work, analogous to current amplification in the transistor, a magnetoresistance amplification effect is proposed in silicon transistor device, where the device current is significantly controlled by magnetic‐field‐manipulated coupling of two p–n junctions in transistor. As a direct consequence, large magnetoresistance of 50 000% with high sensitivity of 50% Oe‐1 is yielded at magnetic field of only 0.1 T. The results not only provide here a new proposal compatible with current semiconductor technology to achieve large magntoresistance at low magnetic field, but also realize magnetic‐field‐manipulated transistor, which is a step for magnetoelectronics.