Universal quantum computer based on carbon nanotube rotators

Abstract

We propose a universal quantum computer based on a chain of carbon nanotube rotators where one metallic plate is attached to each rotator. The dynamical variable is the rotational angle ϕ. The attached plate connected to ground electrostatically interacts with two fixed plates. Two angle positions ϕ = 0, π are made stable by applying a voltage difference between the attached plate and the two fixed plates. We assign ϕ = 0 and π to the qubit states ∣0〉 and ∣1〉. Then, considering a chain of rotators, we construct the arbitrary phase-shift gate, the NOT gate and the Ising gate, which constitute a set of universal quantum gates. They are executed by controlling the voltage between various plates.