ABSTRACT
In principle, a quantum computer is any computing device that makes di-
rect use of characteristically quantum mechanical phenomena, such as en-
tanglement and superposition, to perform operations on data. In a classical
computer, data is handled using bits; in a quantum computer, the data is
handled using quantum bits or qubits for short. A qubit may be realized
using a two-level system which can be represented by an atom or a quantum
dot (QD). Quantum computation relies on the premise that the quantum
properties of particles can be used to represent data, and that quantum
mechanisms can be implemented to execute operations with these data.