Measuring decoherence properties of charge qubits using buried donor cellular automata

Abstract

Quantum-dot Cellular Automata (QDCA) provide an interesting experimental system with which to study the interaction of a charge-based two-level system with the surrounding solid-state environment. This is particularly important given the recent interest in solid-state quantum computers using charge-qubits. We show that many of the properties of these qubits, coupling strength, tunnelling time, relaxation rate and dephasing time can be estimated using a QDCA cell like structure. Calculations are performed for the case of buried donors in silicon but the results are equally applicable to other forms of charge-qubit.