Spin-dependent giant junction magnetoresistance in simple Fe/p-Si(001) Schottky heretrojunction at low temperature

We report on the giant junction magnetoresistance observed at low temperature in Fe/p-Si Schottky heterojunction. The device shows good rectifying characteristics at room temperature and a dual—Schottky as well as magnetic diode—characteristics at low temperature, below 50 K. Formation of a magnetic field-dependent potential barrier due to electrical injection of spin-polarized carriers from the ferromagnetic electrode into the semiconductor is speculated to result in such large junction resistance. The magnetoresistance value is of the order of \(10^{4}\%\) at 10 K and saturates at \(\sim 0.5\,\hbox {kOe}\), showing dual functionality—working as a magnetic diode as well as a magnetoresistive element.