Spin-dependent transport through ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ diluted magnetic semiconductor quantum dots

We theoretically investigate the spin-dependent transport through ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ diluted magnetic semiconductor (DMS) quantum dots (QD’s) under the influence of both the external electric field and magnetic field using the recursion method. Our results show that (1) it can get a $100\%$ polarized electric current by using suitable structure parameters; (2) for a fixed ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ DMS QD, the wider the system is, the more quickly the transmission coefficient increases; (3) for a fixed system length, the transmission peaks of the spin-up electrons move to lower Fermi energy with increasing ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ DMS QD radius, while the transmission of the spin-down electrons is almost unchanged; (4) the spin-polarized effect is slightly increased for larger magnetic fields; (5) the external static electric field moves the transmission peaks to higher or lower Fermi energy depending on the direction of the applied field; and (6) the spin-polarized effect decreases as the band offset increases. Our calculated results may be useful for the application of ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ DMS QD’s to the spin-dependent microelectronic and optoelectronic devices.