Magnetoamplification in a bipolar magnetic junction transistor

We have demonstrated the first bipolar magnetic junction transistor using a dilute magnetic semiconductor. For an InMnAs p-n-p transistor magnetoamplification is observed at room temperature. The observed magnetoamplification is attributed to the magnetoresistance of the magnetic semiconductor InMnAs heterojunction. The magnetic field dependence of the transistor characteristics confirm that the magnetoamplification results from the junction magnetoresistance. To describe the experimentally observed transistor characteristics, we propose a modified Ebers-Moll model that includes a series magnetoresistance attributed to spin-selective conduction. The capability of magnetic field control of the amplification in an all-semiconductor transistor at room temperature potentially enables the creation of new computer logic architecture where the spin of the carriers is utilized.