We have investigated transport properties of electrons in magnetic quantum structures under an applied constant electric field . the transmission coefficient and current density have been calculated for electron tunneling through structures consisting of identical magnetic barriers and magnetic wells and structures consisting of unidentical magnetic barriers and magnetic wells . it is shown that the transmission coefficient of electrons in a wider nonresonance energy region is enhanced under an applied electric field . the resonance is suppressed for electron tunneling through double - barrier magnetic ( dbm ) structures arranged with identical magnetic barriers and magnetic wells . incomplete resonance at zero bias is changed to complete resonance at proper bias for electron tunneling through dbm structures arranged with different magnetic barriers and magnetic wells . the results also indicate that there exist negative conductivity and noticeable size effect in dbm structures 对磁量子结构中电子在外加恒定电场下的输运性质进行了研究.分别计算了电子隧穿相同磁垒磁阱和不同磁垒磁阱构成的两种磁量子结构的传输概率和电流密度.计算结果表明，在相当宽广的非共振电子入射能区，外加电场下电子的传输概率比无电场时增加.对于电子隧穿相同磁垒磁阱构成的双磁垒结构，共振减弱；对于电子隧穿不同磁垒磁阱构成的双磁垒结构，无电场作用时的非完全共振在适当的偏置电压下转化为完全共振，这时的电子可实现理想的共振隧穿.研究同时表明，磁量子结构中存在着显著的量子尺寸效应和负微分电导
