Ion Trap Quantum Computing with Ca+ Ions

Quantum information processing was proposed and considered first by Feynman and Deutsch.(1,2) The requirements for a quantum processor are nowadays known as the DiVincenzo criteria.(3) Storing and processing quantum information requires: (i) scalable physical systems with well-defined qubits; which (ii) can be initialized; and have (iii) long lived quantum states in order to ensure long coherence times during the computational process. The necessity to coherently manipulate the stored quantum information requires: (iv) a set of universal gate operations between the qubits which must be implemented using controllable interactions of the quantum systems; and finally, to determine reliably the outcome of a quantum computation (v) an efficient measurement procedure. In recent years, a large variety of physical systems have been proposed and investigated for their use in