Spin filtering by nanospintronic devices

Amnon Aharony

Dept. of Physics, Ben Gurion University

One of the aims of spintronics is to have devices which polarize the spins of electrons, which enter unpolarized. This talk will present a simple quasi-one-dimensional quantum network (made of quantum wires or by an array of quantum dots), which can serve as such spin filters. The main idea is to combine spin-orbit interactions, whose strength can be tuned by external gate voltages, and the Aharonov-Bohm flux, which can be tuned by an external magnetic field. For broad ranges of these fields, quantum interference allows only one propagating wave function, which has a unique spin state (tunable by the fields). All the other wave functions are evanescent, i.e. they decay as the electron moves in the device.