Chapter One

Table of Contents 1.1 Introduction 1 1.2 Theory: Theoretical Schemes and Algorithms in QMIP 15 1.3 Experimental Techniques 39 1.4 Summary and Conclusion 53 References 84

1.1 Introduction

1.1.1 Similarities and Differences Between Classical and Quantum Mechanical Information Processing

This chapter is designed to benefit the overall scientific community involved in the research and development of quantum mechanical information processing (QMIP). This community itself has evolved, using widely different theoretical and experimental approaches over the years. Unfortunately, the research at present is not realizing its full potential, in part because groups tend to work in isolation from each other and because the overall scientific community shares few common goals. This chapter intends to reduce this communication gap. It also intends to create grounds for workers to familiarize themselves about the various useful technologies that are currently being pursued.

The basics of QMIP were founded along with the birth of quantum mechanics (QM) itself. This happened during the 1920s and 1930s. The enormous success of QM in explaining properties of matter, at solid-state, atomic, subatomic, and other levels, has proven unparalleled in the history of the development of physics. Today, society enjoys the technologies that resulted from these scientific breakthroughs, albeit with little recognition of their origins. Solid-state (SS) quantum physics has resulted in applications as varied and widely available as electronic computers (ECs), mobile communications, space