Quantum Approach to Informatics

CHAPTER 5

PHYSICAL REALIZATION OF QUANTUM INFORMATION PROCESSING

5.1 GENERAL CONSIDERATIONS

Quantum information processing is unique within the field of physics. Despite its rapid growth and the wide interest it has created, its early development has not been driven by any major breakthroughs in experimental science. It arose mainly from an effort to take quantum mechanics seriously. Researchers started to explore the possibilities offered even by the more esoteric nonclassical features of the theory. The entire enterprise may be seen as a systematic exploration of specifically quantum mechanical features, relating human knowledge to the description of measurements as an information-gathering process. Coupled to the contemporary interest in coding, communication, and computing, physics saw a totally new field emerge.

The development should perhaps not have been entirely unexpected. It is a natural direction of exploration when a field of research reaches maturity. After having created the theory to achieve understanding of observed phenomena, the practitioners turn to exploiting the possibilities offered by the newly gained understanding. They start to enquire about which new problems may be solved with the theory and under which experimental circumstances these can be realized. One moves from the stage of analysis to that of synthesis. We have seen the same happen before; the physics of the steering of free electrons and the specialities offered by semiconductor devices have both ...