Gated combo nanodevice for sequential operations on single electron spin.

We present an idea for a nanodevice in which an arbitrary sequence of three basic quantum single qubit gates-negation, Hadamard, and phase shift-can be performed on a single electron spin. The spin state is manipulated using the Dresselhaus spin-orbit coupling intrinsically present in zinc blende materials. The electron trajectory within the device is controlled by voltages applied to a multiple gate system which is deposited on top of a planar semiconductor heterostructure. We present the results of simulations based on iterative solutions of the time dependent Schrödinger equation with the electric field within the entire nanodevice calculated in each time step. We estimate the gate operation times and provide spatial dimensions of the gates allowing for the spin transformations.