Quantum Computing and Quantum Communication with Electrons in Nanostructures

Abstract

If the states of spins in solids can be created, manipulated, and measured at the single-quantum level, an entirely new form of information processing, quantum computing and quantum communication, will be possible. We review our proposed spin-quantum dot architecture for a quantum computer and review some recent results on a deterministic source of entanglement generated by coupling quantum dots. Addressing the feasibility of quantum communication with entangled electrons we consider a scattering set-up with an entangler and beam splitter where the current noise exhibits bunching behavior for electronic singlet states and antibunching behavior for triplet states. We show that spin currents can produce noise even in the absence of any charge currents.