 The proposal of bipolar magnetic semiconductor (BMS) is aimed to realize electrical control of carriers' spin orientation, which is a key scientific problem in developing high performance spintronics devices, since electric ﬁeld can be easily applied locally, in contrast to magnetic ﬁeld.In BMS, the carriers' spin orientation can be controlled simply by altering the sign of the applied gate voltage.Under zero gate voltage (VG = 0), BMS is semiconducting.