A pin junction element includes a ferromagnetic p-type semiconductor layer and a n-type semiconductor layer which are connected via an insulating layer, and which shows a tunneling magnetic resistance according to the magnetization of the ferromagnetic p-type semiconductor layer and the magnetization of the ferromagnetic n-type semiconductor layer. In this pin junction element, an empty layer is formed with an applied bias, thereby generating tunnel current via an empty layer. As a result, it is possible to generate tunnel current even when adopting a thicker insulating layer than that of the conventional tunnel magnetic resistance element.